A Conceptual Study of Implementing Composite Support Towers
for Offshore Wind Turbines. IAN TSE (Cornell University, Ithaca, NY, 14853) JASON COTRELL (National Renewable Energy Laboratory, Golden,
CO, 89401)
Offshore wind
turbine installations have the potential to supply a significant
portion of the nation’s electricity needs; however, the projected
cost of installing wind turbines offshore is significantly more
expensive than current land-based installations in part due to
the high cost of constructing structures to support the turbines
in the water. Support structures in deeper waters (greater than
30m) will likely use relatively expensive truss structures or
floating platforms to support the wind turbine and tower. The
cost of these underwater support structures depends mostly on
the weight of wind turbine and tower. Implementing lightweight
towers made of composite materials could be one way to minimize
the estimated high costs of the underwater support structure.
The objective of this study was to identify a composite design
that had the best combination of weight, stiffness, and cost.
I designed a conventional steel tower as an offshore baseline
model with which to compare the cost and weight of the composite
towers. A set of composite towers of similar geometry and strength
as the baseline steel tower were generated for comparison using
a composite design program and simplified analytical calculations.
The results of the study indicate that it is difficult to create
a lightweight composite tower that is as stiff as a steel tower
without using expensive materials such as carbon fiber. However,
if the diameter of the composite tower is increased, the results
indicate that there is potential to create a lighter tower of
comparable cost. More analysis and optimization of the composite
tower design is required to quantify its potential. In addition,
alterative composite tower geometries and manufacturing methods
should be explored.
A Matlab® Simulation of the Energy Recovery Linac
RF Superconducting Cavity. RANDALL PLATE (Cedarville University, Cedarville, OH, 45314) CARL SCHULTHEISS (Brookhaven National Laboratory, Upton, NY, 11973)
Linear particle
accelerators (linacs) accelerate ions to near the speed of light
in order to conduct experiments on particle collisions. Energy
recovery linacs (ERLs) consist of both a linac radio frequency
(RF) superconducting cavity and an electron ring which can be
used for electron cooling. It is crucial to operate as close
to the resonant frequency of this RF cavity as possible in order
to maintain a proper accelerating field, but factors such as
Lorentz forces and microphonics can detune the cavity. A Matlab
simulation of the cavity provides the ability to analyze these
affects and develop a digital control system to counteract them
and retain the desired electric field gradient. A simulation
of the cavities employed in Tesla, Spallation Neutron Source
(SNS), and the Rare Isotope Accelerator (RIA) was analyzed and
modified to be consistent with the cavity at Brookhaven’s linac
by changing the quality factors, resonant frequencies, and time
constants of the various operating modes. This simulation and
control system will be the foundation for the development of
another, real-time, simulator which will be applied to the physical
cavity. This paper presents the development and implementation
of this simulation and discusses the implications of the results
obtained.
A New GUI for Global Orbit Correction at the ALS Using MATLAB. JACOB
PACHIKARA (University of Texas
at Arlington, Arlington, TX, 76019)
GREGORY J. PORTMANN (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
Orbit correction
is a vital procedure at particle accelerators around the world.
It is very important to have a user friendly application. The
orbit correction routine currently used at the Advanced Light
Source (ALS) is a bit cumbersome and this paper describes a new
Graphical User Interface (GUI) developed for global orbit correction
using MATLAB. The correction algorithm uses a singular value
decomposition method for calculating the required corrector magnet
changes for correcting the orbit. The application has been successfully
tested at the ALS. The GUI display provided important information
regarding the orbit including the orbit errors before and after
correction, the amount of corrector magnet strength change and
the standard deviation of the orbit error with respect to the
number of singular values used. The use of more singular values
resulted in better correction of the orbit error but at the expense
of enormous corrector magnet strength changes. The results showed
an inverse relationship between the peak-to-peak values of the
orbit error and the number of singular values used. The plots
on the GUI help the ALS physicists and operators in understanding
specific behavior of the orbit. It is a convenient application
to use and is a substantial improvement over the previous orbit
correction routine.
Acoustic Doppler Measurement of High Speed Shearing Flow. DAVID
HUBBLE (University of Tennessee, Knoxville, TN, 37916) BRENNAN SMITH (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
The acoustic
Doppler velocimeter (ADV) is an innovative three-dimensional
flow measuring device that relates the phase shift between a
transmitted acoustic signal and its reflected counterpart to
fluid velocity through pulse-coherent processing. Its low cost
and ruggedness make it ideal for measuring in remote locations
such as rivers and tidal regions but its ability to measure high
speed flow remains in question. After analyzing data from an
axisymmetric jet centerline and the exit passage of a hydraulic
turbine, it was determined that an experiment was needed to improve
understanding of how an ADV responds in shearing turbulent flow
and to quantify the bias and errors in measurements from such
flow fields. There are several problems that occur when an ADV
attempts to measure shearing turbulent flow. First, due to range
limitations on the speed settings, high speed flows cannot be
unambiguously measured. Second, due to probe geometry, the vertical
component of the velocity measurement is biased, exhibiting higher
variance than the other two flow directions. To understand how
an ADV reacts to shearing turbulent flow, experiments are being
conducted on an axisymmetric jet at the TVA’s Norris Engineering
Lab. The axisymmetric jet was chosen because it creates a well
understood, predictable flow field with areas of turbulence strong
enough to simulate those found in a hydraulic turbine exit passage.
The experimental design was determined by balancing probe resolution
against the flow capacity and geometric limitations of the test
flume. The geometric limitations caused concern due to the risk
of boundary influence. A four inch jet was chosen. This allowed
four probes to be located within the jet from 2 to 10 feet downstream
with minimal flume boundary interference. There is an inherent
bias in the geometry of the ADV that causes vertical measurements
to contain less noise. Also, there is considerable noise at high
frequencies which indicates an inability to resolve small extremely
small scale turbulence. These data should help engineers decide
when an ADV is appropriate for flow measurement in prototype
settings.
Addition of Wet Turbine Pod and its related heat Exchangers
nto Realativistic Heavy Ion Collider Cryogenic System. CLARENCE
DZUBEY, JR. (CUNY - Bronx Community College, Bronx, NY, 10453)
TOM TALLERICO (Brookhaven National Laboratory, Upton, NY,
11973)
The Relativistic
Heavy Ion Collider (RHIC) consists of two rings of super-conducting
magnets to help guide and focus beams of ions during various
scientific experiments. All magnets must be maintained at a temperature
of 4.5 degrees Kelvin (K). The basic function of the RHIC Cryogenic
System is to maintain the super-conducting magnets in the two
rings of the collider at 4.5 K or below. The Cryogenics Group
(CG) cycles liquid helium throughout the rings in varying amounts
to keep these magnets cold at 4.5 K by removing the heat generated
locally due to currents and heat leakage from its surroundings.
The Cryogenic System (CS) was originally designed for the Isabelle
project, another collider, which required a larger heat load
(~25 kW at 3.8 K) however, it was never completed. The RHIC inherited
this CS but only needs at most approximately 13 kW at 4.5 K of
refrigeration power. The CG has been implementing upgrades over
the last three years to achieve greater system efficiency by
reducing the power usage. This year’s main upgrade consisted
of adding a load turbine and its associated heat exchangers that
are enclosed in a cold box (CB). A turbine is an enclosed rotary
engine that extracts energy from a fluid flow while a CB can
be described as a low pressure vessel providing vacuum insulation
for cryogenic heat exchangers, which are devices built for efficient
heat transfer from one fluid to another. This upgrade would result
in a 1 MW power decrease from 6 MW to 5 MW of compressor power.
We worked on the planning and implementation that went into incorporating
additional control and monitoring instrumentation into the existing
CS for the new turbine and CB. The planning stage included engineering
and design of digital and analog input and output wiring diagrams,
programmable logic card diagrams, and the construction of an
additional human machine interface computer screen. The implementation
stage involved installation of computer racks and wiring along
with analog valves, gauges and sensors.
Advanced Steam Reforming Catalysts for Generating H2 from Natural Gas. GINA FAZIO (University of Illinois at Urbana Champaign, Urbana-Champaign, IL, 61801) DR. MAGALI FERRANDON (Argonne National Laboratory, Argonne, IL, 60439)
Reforming of
natural gas at the point-of-application is one option being pursued
to provide H2 for use with fuel cell systems being developed
for distributed power applications. New reforming technologies
will be required for these integrated fuel processor-fuel cell
systems. A critical component of these fuel processors is the
reforming catalyst, which promotes the conversion of the natural
gas to H2. Rhodium supported on an oxide substrate, such as alumina
or ceria, is one of the most effective catalysts for reforming
natural gas. Unfortunately, Rh is an expensive precious metal
and, hence, the cost of a Rh based catalyst is an issue. Optimizing
the Rh loading is critical to minimizing catalyst cost. The objective
of this project is to investigate the effect of Rh loading on
the performance of Rh supported on a lanthana-modified alumina
for the steam reforming of methane, the primary component of
natural gas. Three different Rh loadings were investigated: 1,
2, and 5-wt%. The catalysts were tested in a microreactor system
using either a 3:1 mixture of H2O:CH4 or a reformate containing
1% CH4 at 600-950°C and gas-hourly space velocities (GHSV) of
20,000-70,000 h-1. At a GHSV of 20,000 h-1, similar CH4 conversions
and H2 yields were observed for all three Rh loadings for all
conditions investigated. However, at a GHSV of 60,000 h-1, a
significant drop-off in performance were observed with the 1
and 2-wt% but not the 5-wt% Rh catalysts.
An Investigation of the Optical Detection of Cellular Metabolic Activity. KELLY CHRISTIAN (University
of Tennessee, Knoxville, TN, 37996) JUSTIN BABA (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
The clinical
challenge of preventing life-threatening vascular complications
after liver and other organ transplants necessitates a means
for continual post-operative monitoring for rejection, infection,
and normal function assessment. Current methods, which utilize
crude systemic measures such as volume of urine output and serum
markers for cellular injury, are woefully insufficient. At best,
these serve as indirect, time-delayed measures of tissue viability.
Additionally, these techniques do not provide continuous, real-time
monitoring and thus are inadequate for timely assessment that
could enable life saving interventions. To address these inadequacies,
the development of a device for continuous real-time tissue metabolic
assessment is underway. Currently, an investigation is in progress
to determine the appropriate equipment needed to produce a device
that can track the ratio of two fluorescent coenzymes that are
involved in cellular metabolic activity, NADH and FAD. It is
anticipated that the NADH /FAD ratio will stay constant for normal
function and increase considerably in the case of abnormal function.
Therefore, the detection of a noticeable increase would suggest
an early change in tissue viability, i.e. before irreversible
organ damage occurs. Before this can be explored, an optical
probe must be developed that can appropriately detect and measure
the concentrations of NADH and FAD. A device was designed and
tested on a spectrophotometer with several different light sources,
such as a tungsten halogen, a UV fluorescent lamp, and multiple
LEDs (Light-Emitting Diodes), to determine if one of the sources
could detect high concentrations of the coenzymes in vitro. A
model probe was also constructed, where the samples were tested
with the photodiode detector. The results presented show that
NADH and FAD fluorescence was visibly observed when the light
sources simply illuminated the samples, however the fluorescence
was unable to be detected with all but one of the light sources
used. This indicates that the samples were fluorescing, but the
spectrophotometer and the probe were unable to detect fluorescence
due to low sensitivity in UV and near visible range. Future work
must be done to determine a proper light source that can detect
NADH and FAD suitably. Once the probe is complete, it must be
tested for the detection of anticipated physiological concentrations
in vitro and for conducting ex vivo studies using excised organs
before finally proceeding to live in vivo studies.
Anemometer Standoff. NICHOLAS JOHNSON (University
of Colorado at Denver, Denver, Co,
80112) HAL LINK (National Renewable Energy Laboratory, Golden,
CO, 89401)
Accurate
wind speed measurements are critical in the analysis of wind
turbine power performance. Common industry practice is to measure
wind speed using a cup anemometer that is mounted in a position
where the supporting tower distorts the measurement. It is
ideal to mount the anemometer on top of the tower. Sometimes
this is no practical and must be mounted on a boom, that supports
it away from the tower, far enough to limit distortion errors
to 1%. A theoretical model has been used to quantify where
a distortion will occur with respect to the tower. However,
some researchers have recently speculated that the theoretical
model inaccurately predicts the distance from the tower where
the 1% distortion error occurs. The objective of this project
was to experimentally measure and quantify this distortion
and thereby validate or disprove the model. To achieve this
objective, a test was configured where one anemometer was mounted
above a triangular lattice tower to measure the undistorted
wind speed. On the same tower a boom-mounted anemometer was
mounted below the top of the tower to measure the distorted
wind speed. Data were collected by the boom-mounted anemometer
at different "standoff" distances. Standoff is the
ratio of the separation of the anemometer and the tower to
the width of the tower. Data were sorted by wind direction
in order to plot where the critical distortion occurs - when
the anemometer is directly upwind of the tower. This value
was reported. A second tower was requisite to quantify the
vertical spacing effects between the top-mounted and the boom-mounted
anemometers. This test measured distortion effects for three
configurations: at a standoff of 2.31, the model predicts a
distortion error of 1.6%, the test indicated 3.2 %; at a standoff
of 3.47, the model predicts a distortion of 0.9%, the test
indicated 2.6%; at a standoff of 4.62, the model predicts a
distortion of 0.6%, the test indicated 1.6%. Based on these
test results, NREL has concluded that the model inaccurately
predicts the distortion. To obtain accurate wind speed measurements
with boom-mounted anemometers a larger than predicted standoff
is required. Results to date are limited to relatively small
amount of standoff distance points, more research is needed
to create an acceptable model.
Assessment of Biometrics System. KWOK
WING LEE (Stony Brook University, Stony Brook, NY, 11794) UPENDRA S. ROHATGI (Brookhaven National Laboratory, Upton, NY, 11973)
Biometric
systems are used to authenticate users based on their biological
characteristics such as face, voice, fingerprint, and hand
geometry. This kind of identification system provides the user
with logon convenience and extra protection against theft.
The Russian Academy of Sciences Institute of Applied Physics
is involved with the project and they are developing a software
development kit (SDK), where others can use this product and
create their own biometric identification system. To evaluate
the quality of their product, a Biologin program was created
using C++ programming and other technologies such as Microsoft
Graphical Identification and Authentication Dynamic Link Library
(MSGINA DLL). Communication with the Russian institute was
established daily via internet, to provide them with feedback
on their SDK and documentation. The goal of creating a Biologin
was to determine if the SDK is useable and if the product can
be sold to consumers. Product documentation is very important
for a SDK but was lacking in the product and constant communication
was required. Testing of the recognition system was very accurate
and accounted for only a 3% error rate. It is difficult to
work with another country because of language barriers and
the time difference. This was a learning experience for the
Russian Institute because they must develop software products
that can compete with existing ones in the market.
Bipolar Plate Design and Manufacturing for Proton Exchange Membrane Fuel Cells. RACHEL BACKES (Colorado School
of Mines, Golden, CO, 80401) JOHN TURNER (National Renewable
Energy Laboratory, Golden, CO, 89401)
The proton
exchange membrane fuel cell (PEMFC) is the preferred candidate
for future fuel cell automobiles. Metallic bipolar plates have
the ability to improve this type of fuel cell. This project
focuses on how stainless steel bipolar plates can be produced
and designed for use in PEMFCs. The plate material considered
is type 446 stainless steel. Flow patterns are designed to
be stamped into the plate through application of rubber pad
forming techniques. Dies are designed for the stamping process,
and preliminary testing is done with substitute materials.
The results of preliminary testing were successful, particularly
with the softest backing material used. Seals required for
implementation in a fuel cell stack are also designed. The
result of this project is a set of preliminary designs for
the production and use of stainless steel bipolar plates in
a PEMFC.
Building an Atomic Layer Deposition (ALD) System for the Coating of Ceramic
Rods. MATTHEW LEWIS (Iowa State University, Ames, IA, 50013)
GREGORY KRUMDICK (Argonne National Laboratory, Argonne, IL, 60439)
Many new
types of technology are being introduced in today’s world,
but few of them offer a wider variety of uses than Atomic Layer
Deposition (ALD). ALD makes it possible to deposit a layer
of film as thin as one atomic layer on a surface and allow
maximum control of thickness. With this type of layer control
the technological possibilities are virtually endless. The
ALD system currently being built in building 362 at Argonne
National Laboratory needed to be designed to coat ceramic rods
so different materials could be tested on them for strength
and thermal efficiency. To accomplish this task we used the
existing ALD system as a template and scaled up the new system.
Many parts were fabricated by central shops using CAD drawings
from Microsoft Visio that were specialized to fit the new system.
The design and engineering phase of the new system is nearly
complete and the fabrication phase has already begun. The system
is scheduled to be finished in late January at which time it
will be leak checked and ready to coat materials. The system
is also being designed so that it is flexible, in that when
ceramic rod testing has been completed, the system will be
able to be used for many other types of applications.
Cellulose Breakdown Using a Dry acid Catalyst. KEVIN
JACKSON (University of Illinios
at chicago, Chicago, IL, 60645) CHRISTOPHER MARSHALL (Argonne National Laboratory, Argonne, IL, 60439)
With the flux of current gas prices, energy security has become
top priority for the United States in recent months. Because
of current non-renewable fossil fuels located in unstable
regions of the world, America is now looking into renewable
alternative sources of energy to fuel our nation’s automotive
fleet and provide a means of cheap energy. A successful alternative
energy source would allow America to become independent of
the unstable regions of the world that currently produce
over 80% of the worlds fossil fuels. Ethanol and Hydrogen
fuel cells are among the hopefuls that will one day replace
gasoline as the fuel that feeds our gas tanks. Between those
two, Ethanol production is disputed to be the best option
towards supplying our nation’s needs. In Brazil, ethanol
Production has already replaced 40% of their fueling needs.
However, ethanol production is much easier in South America
due to climate conditions. They use sugar cane, which is
highly made up of sugars like glucose, to produce ethanol.
To produce ethanol practically in the U.S. we will need a
method of converting the cellulose in corn into ethanol since
sugar cane can’t be grown in our climate. Methods: In
my experiments in the lab so far, I have worked with my supervisor
Chris Marshall to figure out a way to break the cellulose
chain into glucose. The current idea centers on the use of
a dry-acid Zeolite catalyst. The proposed catalyst is a three
dimensional molecule that has a monolithic structure. Inside
the pores of the zeolite is where the reaction takes place.
However, the pore size of the zeolite is too small for the
large chain of cellulose to fit through. So we have tried
using partial acid hydrolysis to break the cellulose into
small enough fragments to fit inside the zeolite. Then the
reaction is observed and later analyzed for Glucose. Results and Discussion: Trace
amounts of glucose was detected from the experiments. In
each case, the Glucose was produced at the last hour of extraction.
The Product also occurred only in runs that included dilute
acid solution as well. Whether or not the product is caused
by the catalyst itself is yet unknown. We have produced some
glucose and further refining of our methods is needed to
further optimize the conditions and possibly produce more. Conclusion: As
of yet, the dry acid catalyst has not produced any valuable
amounts of product to prove practical. Further study is needed.
Characterization of Superconducting Splices. MEGAN
MALLETTE (Valparaiso University, Valparaiso, IN, 46383) CHRISTOPHER REY (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
High temperature
superconductors (HTS) are materials that have no resistance
to electrical current at temperatures below the transient temperature,
Tc, and are therefore able to conduct much higher currents
than traditional wire, in a much smaller area. HTS have the
potential to greatly increase electrical efficiency in a number
of applications, but it is necessary to first fully characterize
the behavior of splices (i.e. electrical joints) before incorporating
HTS wire into applications in order to minimize joint failure.
During this investigation, splices of superconductors to be
tested were fabricated by varying the type of solder, surface
preparation, joint overlap area, and thermal cycle. Each splice
consists of a series of seven lap joints. After fabricating
each splice, a range of currents are applied to the splice
and voltage measurements across each joint are used to calculate
the resistance of each joint for the range of currents tested.
While holding all other variables constant, the Sn60-Pb40 solder
outperformed the In66.3-Bi33.7 solder in every test. Testing
splices with no surface preparation resulted in poor mechanical
joints that were unable to handle the stress of testing, showing
the importance of surface preparation and oxide removal. Of
the two types of fluxes tested, the paste flux outperformed
the ruby fluid flux with all other variables constant in every
test, except one splice in which the HTS was damaged by the
temperature of the soldering iron. Results from varying joint
overlap areas showed that larger contact areas decrease the
joint resistance, as expected. Surprisingly, there was little
difference between successive thermal cycles due to the stress
of repeated temperature changes. Further testing on additional
types of solders, fluxes, and joint overlap areas would result
in a more comprehensive report on splices of HTS. Other variables
that need to be considered in further testing of splices are
the effects of varying magnetic fields, temperature dependence,
and different types of mechanical stress.
Collection, Analysis, and Archiving Heavy Truck Driving Characteristics and
Duty Cycles to Support the Evaluation of Benefits of Energy
Efficiency Technologies. JOSEPH MASSIMINI (Purdue University, West
Lafayette, IN, 47906) GARY CAPPS (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Despite common
beliefs, commercial vehicle energy performance on highways
is not well known. Ever changing hours of operation, anti-idling
regulations, traffic situations and construction work make
it difficult for drivers to have a true situational awareness
of driving characteristics on highways. Understanding of these
characteristics is often obtained through qualitative means.
A quantitative profile of driving behavior of heavy trucks
does not exist. Generation of duty cycles that reflect real
world driving would aide in creating such a profile. Sensors,
autonomous to the driver, mounted on active fleet tractor trailers
collecting kinetic, kinematics, human factor and environmental
information will provide the data necessary to generate these
duty cycles. Additionally, half the tractor-trailers will be
fitted with Next Generation Single Tires (NGSTs) as opposed
to standard dual tires to observe any improvements in fuel
efficiency. This project involved extracting and analyzing
the duty cycle data collected during the Pilot Test and creating
and testing a prototype sensor suite for the Field Test that
includes both Controller Area Network (CAN) and RS-232 type
connections, requiring not only specific programming in the
Data Acquisition System (DAQ), but also special CAN cables,
RS-232 connectors and signal conditioning modules. ORNL worked
with the DAQ vendor to specify and create the necessary software
and hardware needed for integration into the prototype. This
project also had to consider the fact that active fleet tractor
trailers with a single driver typically operate 11 hours a
day. Each channel collected and stored in the DAQ is collected
at 16 bits per Hertz, thus a very large amount of data will
be collected in a very short period of time. Methods were developed
for formatting, organizing and archiving this large amount
of data using custom Visual Basic software. At vehicle launch
duty cycle data will be collected with the custom sensor suite,
and will be archived and stored in an accessible location using
the created software and can be used for validation, research
and development of energy efficient technologies.
Collection and Transmission Systems Cost and Performance Model for the Baseline
Offshore Wind Farm. AMY BOWEN (Baylor University, Waco, TX, 76798) JIM GREEN (National Renewable Energy Laboratory, Golden, CO,
89401)
The National
Wind Technology Center (NWTC) of the National Renewable Energy
Laboratory (NREL) has undertaken a series of concept studies
to evaluate the cost and performance of offshore wind farms.
One of these studies will evaluate the power losses experienced
throughout the electrical power collection and transmission systems
as well as the cost of the system components and their installation.
A hypothetical system was designed based loosely on the Horns
Rev offshore wind farm. This system was then sent out to manufacturers
with requests for electrical and cost data on the submarine cables
and transformers. Upon discovering that the electrical data available
for submarine cables is scarce, a very basic method of loss analysis
was developed using three parameters: conductor resistance, ampacity,
and power loss at capacity. The total losses are divided into
two groups: losses that are modeled as a quadratic term which
varies with current, and a base loss that is assumed to vary
little with current, and is thus modeled as constant. In the
model, both costs and losses are listed in per meter values to
account for parameter variability. Power losses varied between
cables from different manufacturers and also between different
wind farm layouts. The cost of cables varied widely between different
manufacturers as well, with one manufacturer’s cable more than
two times higher than another’s. The results obtained in this
study will be applied to the overall concept study.
Compact Nanosecond High Current Pulser Design. MICHAEL
MALLO (University of Oklahoma, Norman, OK, 73019) SOREN PRESTEMON (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
A pulser is
an electronic circuit which generates a high voltage or current
pulse with a very short pulse-width. Pulsers can be implemented
using various topologies, such as Marx Generators, capacitor
banks, coaxial transmission lines, helical lines, striplines,
and Blumleins. The goal of this project was to review basic pulser
theory and to design, test, and compare several pulsers using
various topologies. The final design should deliver a repeatable
pulse greater than 1 kA with 10 ns or less pulse-width to a 1
Ohm inductive load (high field microcoil) and be small enough
to allow for insertion into an ultra high vacuum accelerator
environment. The pulser topologies tested were capacitor bank,
coaxial transmission line, stripline, and parallel plate Blumlein.
The capacitor bank produced an output voltage of 289 V with a
ringing frequency of 17.9 MHz, corresponding to a positive voltage
pulse-width of 28 ns. The load impedance of this circuit is unknown.
The coaxial transmission line was expected to produce an output
voltage pulse of 500 V with a pulse-width of 13.2 ns; the actual
output was 500 V, but with a pulse-width of 11.8 ns. The stripline
was expected to produce a 1 kV 4 ns voltage pulse through a 1
O inductive load. The parallel plate Blumlein was expected to
produce a 1 kV 1.2 ns voltage pulse through a 1 O inductive load.
However, the stripline and Blumlein both produced far less voltage
than anticipated and voltage pulse-widths of just over 10 ns.
Three factors may have lead to this inconsistency in predicted
versus measured pulse-widths. First, the diagnostic tool used
to measure the stripline and Blumlein voltage pulses was a Tektronix
P5102 1 kVRMS 100
MHz 10x high voltage probe. The 100 MHz bandwidth prevents the
probe from accurately measuring pulse-widths shorter than 10
ns. Second, the short lengths of these lines may have lead to
a greater prominence of end effects, or variations in the electric
and magnetic fields at the ends of the transmission lines, in
the output pulses. Third, the low 1 O load impedances combined
with the stray inductances may have caused longer than expected
pulse rise times. The latter two factors warrant further investigation
to better understand what electrical and geometric properties
lead to end effects and long rise times, and to what extent they
affect the output pulse.
Comparing Predicted and Actual Energy Cost Escalation in Energy Savings Performance
Contracts. LARRU KISER (Ferrum College, Ferrum, VA, 24088)
JOHN A. SHONDER (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Energy Savings
Performance Contracts (ESPC) are a method of financing energy conservation
projects using the energy and energy-related cost savings generated
by the conservation measures themselves. In Federal ESPC, an energy
services company (ESCO) obtains financing and installs energy conservation
measures at no up-front cost to the government. The government pays
the ESCO from the cost savings generated, and the ESCO uses these
payments to repay the financing. Since energy prices are volatile,
ESPC contracts usually agree to escalate energy cost savings at fixed
rates. The most common source for escalation rates is the U.S. Energy
Information Agency (EIA), which publishes annual predictions for
electricity and natural gas price escalation for the four U.S. census
regions. The purpose of this project was to determine how well the
predictions from the EIA matched the actual escalation of electricity
and natural gas prices from 1998 to 2004 for the four census regions.
It was discovered that the escalation of electricity rates was overestimated,
with the exception of region four (Western U.S.), and the escalation
of natural gas rates was underestimated. Based on statistics from
the U.S. Department of Energy’s Super ESPC program, a typical ESPC
project was defined, and the difference between actual and contracted
cost savings was calculated for each of the four regions.
Comparison of Intrabeam Scattering High Energy Approximations, and Equilibrium. ROBERT OWENS (North Carolina A&T State University, Greensboro, NC, 27411) MIGUEL FURAN (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
The International
Linear Collider (ILC) is a particle accelerator being designed
with the hopes of exploring higher energy particles in the universe
that have never previously been accessible. Two of the major
components of the ILC are the electron and positron damping rings,
which serve the purpose of shrinking the emittances of the beams.
There are several competing processes that affect the beam emittances.
Synchrotron radiation damping serves to decrease the emittances.
A major contributor to emittance growth is a phenomenon called
Intrabeam Scattering (IBS), wherein particles within a single
bunch Coulomb scatter off one another, thereby causing the beam
emittance to increase. The IBS emittance growth rates are calculated
using computer codes, and often it is too time consuming to use
the full theory of IBS. In order to calculate IBS growth rates
in the most efficient manner, several high-energy approximations
to the full theory have been developed for the energy regime
of the ILC. It is important to find the most accurate approximation.
We analyzed three approximations of IBS using the software package,
Mathematica; Bane’s approximation, a new Diagonal Matrices approximation,
and a recent CIMP one-log approximation, while attempting to
develop a better two-log approximation to the CIMP formulas.
We also analyzed the equilibrium emittances of the beams at different
charges to determine if the transverse emittances, bunch length,
and energy spread would meet the necessary requirements for the
ILC. After comparing the various approximations, the Diagonal
Matrices approximation proved to be the closest approximation
to the full theory of IBS.
COMPARISON OF THREE-PHASE AC/DC CONVERTERS IN A WIND TO HYDROGEN SYSTEM. JOSHUA PRICE (University of Colorado
at Boulder, Boulder, CO, 80303) CHRISTOPHER PINK (National Renewable
Energy Laboratory, Golden, CO, 89401)
Efficient production
of hydrogen from wind power can be achieved by direct coupling
of a variable-speed three-phase wind turbine to an electrolyzer
with a high quality three-phase ac/dc rectifier interface. This
paper compares three different topologies of three-phase high-quality
rectifiers for use in a wind to hydrogen system. A six-pulse
phase-controlled rectifier, a single-switch unidirectional ac/dc
buck converter, and a single-switch ac/dc single-ended primary
inductance converter (SEPIC) are developed and simulated using
software-modeling techniques to calculate power output and efficiencies
determined by wind turbine and electrolyzer operational characteristics.
Software simulations indicate that the single-switch ac/dc SEPIC
exhibits an increase in power production of 25% in the lower
25% of usable wind speeds over the single-switch ac/dc buck converter,
and an increase in power production of 5% in the lower 10% of
usable wind speeds over a modified six-pulse phase-controlled
rectifier, with less cost and comparable efficiency. This work
is part of a larger project that investigates a methodology to
maximize off-grid wind to hydrogen production with a power electronics
interface.
Completing phase iii of chipmunk electrical packaging upgrade. JULIAN DIAZ (Bronx Community College, Bronx, NY, 10453) VINCENT CASTILLO (Brookhaven National Laboratory, Upton, NY, 11973)
Chipmunks are
radiation monitoring devices used by the Collider Accelerator
Department (C-AD) at Brookhaven National Laboratory (BNL) that
detect radiation by means of an ionization chamber which generates
a current that is proportional to the radiation. The current
is converted to a frequency which is also proportional to the
radiation. Different levels of radiation are used to create interlocks
on the C-A machines. Chipmunks were developed at Fermi National
Laboratory (FNAL) in the early 1980s and for the past 26 years
have been effective as the detectors in the radiation monitoring
system for the C-AD at BNL. They were designed with 1980s technology
which included extensive hand-wiring and some of the components
are actually obsolete. An engineering upgrade was started three
years ago with the help of Community College students from the
Community College Institutes (CCI) summer student program at
BNL. A backplane was designed to replace hand-wiring and printed
circuit boards (PCBs) were redesigned with readily available
components. This project is focused on the design of circuits
that will complete the upgrading process. Such circuits include
a PCB for the indicators lights; a PCB for the front panel indicators;
a PCB for the interlock circuits and completion of the backplane
wiring. With all this circuitry in place the upgraded chipmunk
will be ready for testing.
Computer Aided Engineering in the Development of the Electron Beam Ion Source
Electrostatic Components in the Low Energy Beam Transport Region. GAVIN MCINTYRE (Rensselaer Polytechnic Institute, Troy, NY, 12180) LOUIS SNYDSTRUP (Brookhaven National Laboratory, Upton, NY, 11973)
The Electron
Beam Ion Source (EBIS) is the new pre-injector system for the
Relativistic Heavy Ion Collider (RHIC) and will outperform the
Tandem van de Graff which is the current ion source for RHIC.
The EBIS is more versatile, with the ability to produce myriad
stable ion species from the noble gases to uranium. Deflectors
(steering/minor focusing) and quadrupoles (focusing/defocusing)
ensure the beam quality and are developed using computer aided
drafting and engineering software. The analysis is crucial to
the success of the deflector and quadrupole designs; thus simulations
constructed in analytical software (Kobra) are developed to ensure
design integrity. The Adaptor Deflector is the initial steering/focus
device that is mounted concentrically to the upstream ion lens.
The deflector consists of electrode pairs with equivalent potentials
that are mounted either parallel or alternating. Various designs
were modeled using Pro/Engineer and were comprised of two to
eight electrode pairs. The investigated designs included: the
split cylinder, the dual dipole (two dipoles offset from one
another), and 8/16 congruent, electrode arrangements in order
to ascertain the design that produces the least aberrations to
the ion beam. The functionality of the deflector designs were
simulated with a theoretical beam in the electrostatic analysis
software, Kobra, and the 16 electrode deflector produced the
most desirable qualities. Three quadrupoles are located in the
Low Energy Beam Transport (LEBT) region of EBIS; the two simulated
designs were a basic quadrupole triple and a Helical Electrostatic
Quadrupole (HESQ). The triplet is composed of three inline quadrupoles,
with electrode pairs of equivalent electric potential which focuses/defocuses
the ion beam in two axial directions. The electrodes are oriented
by a stainless steel framework and ceramic standoffs that act
as insulators for the grounded vacuum vessel. The quadrupoles
are offset from the vacuum chamber using swivel bolts that aid
in mounting. The design incorporates two spring-loaded feedthroughs
per quadrupole, which supply the voltages to a divided contact
pad that is directly connected to the electrodes by solid wire.
The HESQ has four helical electrodes held concentric in a grounded
vacuum vessel and offer more locations for focusing/defocusing
than the triplet while spanning a shorter length. The electric
fields the quadrupoles produced were tested using the electrostatic
capabilities of Kobra by applying various potentials to the electrodes;
both resultant fields were adequate for focusing/defocusing the
EBIS but the HESQ was superior to the triplet.
Controls Engineering for a Compact Crystal Positioning System. PRISHANTHA
DUNSTAN (Columbia University, New
York, NY, 10027)
CHRISTINA HOFFMANN (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
The ability
to manipulate a sample for research and development has always
been a basic essential. When sample size shrinks to the micro-scale
and the environment for analysis proves unsuitable for direct
human interference, the ability to carefully and accurately control
the sample becomes much more difficult. In this case a positioning
system for aligning and moving the samples remotely is desired.
Such a device was constructed by Square One Systems in collaboration
with the Spallation Neutron Source at Oak Ridge National Laboratory.
Based on a tri-sphere approach, a series of linear actuators
are employed to perform linear and spherical motions around a
center point. The scope of this project was multifold: The individual
motors of the instrument were calibrated and aligned. Once completed,
the instrument was hardwired into a computer for control through
LabVIEW software. The controls software was designed to mimic
the operation of a goniometer, such that the sample could be
rotated through two angles, the second angle being dependent
upon the first. The equations of motion used enable sample rotation
such that the crystal’s position remains fixed while the motors
move around it. Since the samples will be subject to neutron
beam exposure with dimensions as small as 100m x 100m, ensuring
that the crystal does not leave the beam when rotating will be
essential to collect meaningful data. The controls also provide
numerous calibration functions, enabling re-centering and adjustment
of the sample after loading. The software calculates limits of
rotation, preventing over rotation and possible dropping of the
sample. Virtual images of the sample plate provide a visual for
the scientist, due to the fact that the sample chamber will prevent
direct view of the sample. This new instrument provides several
advantages over the current sample positioner on the market (the
hexapod). Using innovative Piezo motors, the instrument can manipulate
the sample with zero backlash, ensuring accurate manipulation.
The instrument also allows for easy sample changing, since the
sample plate is not permanently fixed to the instrument. Because
the software allows for repositioning of the sample, it provides
much room for time-saving methods. For example, if a sample pin
were used, such that 3 samples were loaded (one at the tip, one
1/3 from the tip, one 2/3 from the tip), the instrument could
manipulate 3 samples sequentially without the need to reload.
Design and Construction of an RF Plasma Source. JOHN CARR
(University of Illinois
at Chicago, Chicago, IL, 60601) RICHARD VONDRASEK (Argonne National Laboratory, Argonne, IL, 60439)
An RF plasma
source is being developed to provide a 1+ ion beam for the Californium Rare Ion Breeder Upgrade. The 1+ beam
will be injected into the Electron Cyclotron Resonance ion source,
at the Argonne Tandem Linear Accelerator System, and charge bred
to n+. An existing plasma source, no longer being used, was redesigned
and modified to conform to new specifications. The RF plasma
source consists of a 29 ml high-temperature quartz ion bottle.
Gas is admitted to the plasma chamber through the ion bottle
using an insulated tip and sealed with an o-ring. The bottle
is mounted to a 5 inch round base, also sealed with an o-ring.
Beam extraction is provided by a 30 kV puller mounted to the
base opposite of the ion bottle. The source is designed to use
up to a 500 MHz RF signal to ignite the plasma and create the
ion beam. Redesigning and retrofitting a currently available
unit was a time and cost effective way to construct a suitable
plasma source.
Design and Implementation of a High Availability Distribution
Layer In a Campus Environment. MANGAL
TYAGI JR. (Prairie State College, Chicago Heighs, IL, 60411)
AJ TEMPROSA (Brookhaven National Laboratory, Upton, NY, 11973)
The implementation
of a robust, scalable, and fault tolerant network is dependent
on logical and physical segmentation of workgroups to provide
compartmentalization in event of network failure. The Cisco hierarchical
model simplifies the task of building a reliable, scalable, and
cost-efficient hierarchical internetwork by introducing a modular
approach to the design and functionality of each network component.
A distribution layer provides policy-based connectivity for workgroup
access without having to route local data through the core or
backbone of the network. By determining the fastest or best path
to transmit data, the distribution layer will also send non-local
requests to the high-end core, which will then transport the
request at high data transfer rates to the correct service. Several
policies provided at the distribution layer include packet filtering,
quality of service (QoS), virtual LANs (VLAN), and manipulation
of network traffic, which altogether contribute to exerting control
over network transmissions and what goes in and out of the network.
In order to improve Brookhaven National Laboratory’s (BNL) network,
a third distribution layer (DL-3) will be configured and deployed
which will be attached to the core at high transfer rates and
redistribute network data across a portion of the BNL campus.
DL-3 will have redundant chassis consisting of the Cisco 6500
series, multi-layer switches, and dedicated power distribution
unit (PDU) feeds. In addition, port aggregation is a technology
that is implemented to provide higher bandwidth, and will also
serve as a backup if a link fails. Before the deployment of DL-3,
the components, such as the supervisor engines and multi-layer
switches, have to be properly configured. The configuration process
includes conversion of the Cisco supervisor engines from hybrid
to native mode, assigning VLANs and network addresses, and establishing
the spanning tree root. Once DL-3 is configured, it is connected
to the network to start servicing the BNL campus similar to the
other two distribution layers. The deployment of DL-3 will provide
more reliable connectivity at the BNL campus by reducing the
amount of hosts exposed to network failure. The work being performed
is part of an ongoing effort to BNL’s network reliability and
performance.
Design Assistance for Renovation and New Construction at Red Rock Canyon
National Conservation Area Using Building Energy Simulation. BENJAMIN
BARNES (University of Illinois
at Urbana Champaign, Urbana-Champaign, Illinois, 61801)
ROBI ROBICHAUD (National Renewable Energy Laboratory, Golden,
CO, 89401)
The Federal
Energy Management Program Technical Assistance team at NREL used
eQUEST software to help the Bureau of Land Management in their
attempt to reach and exceed the goals of the 2005 Energy Policy
Act in their new visitor center and renovated offices at Red
Rock Canyon National Conservation Area. EQUEST was chosen for
its intelligent defaults and its DOE-2 engine, which has been
well validated against real buildings. Weather data collected
on site was used for simulating external loads and visitation
data from the current visitor center was used to generate internal
occupancy loads while other internal loads were largely eQUEST
defaults, except infiltration, which was adjusted to account
for the door use patterns of a visitor center. The heating, ventilating
and air conditioning (HVAC) equipment in the design involves
a dedicated outdoor air system (DOAS) serving all zones and several
recirculating, terminal units. The outdoor air load was simulated
by assigning the DOAS to a few central zones and giving it the
entire building outdoor air requirement while the recirculating
units served the zones they were specified to with no OA load.
Evaporative cooling (EC), on-off, two step and continuous daylighting,
moveable insulation, dual speed compressors and a deeper Western
overhang were all simulated. The EC and daylighting achieved
the majority of the savings (21% and 8% of total building energy,
respectively) while the results for the other measures suggested
that they can likely be ignored. It is recommended that water
conservation issues with EC be seriously investigated. Two step
daylighting controls should be implemented and, if it proves
feasible, combined with EC. The moveable insulation should be
avoided as it would introduce maintenance issues and actually
has a net detriment to energy use. The model, in the future,
should be further validated concerning its HVAC approximations
and used to assist in peak load management. Also, to be of greatest
benefit, it must be kept up to date with current design development.
Design of Blade Rotation System for a Large Wind Turbine Blade Test Stand. MICHAEL SMITH (Portland State University, Portland, OR, 97201) JASON COTRELL (National Renewable Energy Laboratory, Golden,
CO, 89401)
Wind turbine
blade testing is a key element in the development and success
of the blade manufacturing industry. Testing is necessary to
achieve higher reliability and meet international certification
requirements. NREL (National Renewable Energy Laborotories) tests
blades on both faces by mounting the blade on a test stand and
applying static loads. The blades must be rotated between tests
to apply loads to a second face. The objective of this study
is to create and evaluate design options for a blade rotation
system. Project deliverables include design specifications, graphic
models, and cost estimates. The primary components of the rotational
system include large adaptor plates, a rotational guide, and
a drive. The focus of the study is on the design and selection
of the rotational guide. Two main concepts were developed for
comparison; one in which the blade is mounted to a heavy duty
slewing bearing and one that uses calipers with rollers to support
and guide blade during rotation. The results of this study indicate
that the caliper design is likely to be a more expensive and
complicated choice. However, the caliper design offers options
for scalability and modularity that may make it more cost effective
in the long term.
Design Study of Temperature Stabilization of the Analyzer Array of the High
Energy Resolution Inelastic X-Ray Spectrometer of the Advanced
Photon Source. JUSTIN BUELL (Montgomery College, Rockville, MD, 20850) BRANISLAV BRAJUSKOVIC (Argonne National Laboratory, Argonne, IL, 60439)
Through the
use of the high energy resolution inelastic x-ray (HERIX) spectrometer
at the Advanced Photon Source (APS), vibrations in the lattice
structure of various materials can be studied. The instrument
consists of nine detector-analyzer pairs, a vacuum chamber, and
a support structure for the entire instrument. X-rays from the
APS beamline, scattered by a specimen through the vacuum chamber,
are reflected and focused by the analyzers through a collimator
and into a series of corresponding detectors which measure the
properties of the photons. Due to the high cost of vacuum compatible
components, it is more economical to place the analyzers outside
of the chamber than inside it. Because thermal expansion due
to temperature fluctuations in the hatch in which the spectrometer
is located will compromise the geometric alignment between the
optical components of the spectrometer, it is necessary to stabilize
the temperature of the analyzers before the instrument can be
calibrated. Using SolidWorks, a model of an enclosure and cooling
channels for the analyzer array was developed. Expanded Polystyrene,
a type of Styrofoam, was the selected material for the enclosure
because of its optimal thermal properties. The enclosure was
designed to eliminate heat transfer by free convection and minimize
conduction to the analyzers. The cooling channels will consist
of a copper tube through which water at a controlled temperature
will flow and a series of copper pads, onto which the tube will
be brazed, that will be mounted onto the support plate of the
analyzers to improve thermal conduction between the analyzers
and the cooling water. Finite element analysis of transient heat
transfer was performed on the model assuming the hatch temperature
to be a sinusoidal function of time based on measurements from
a similar hatch. The results of the analysis indicated that the
enclosure alone would not sufficiently stabilize the temperature
of the analyzers, but that the enclosure and cooling infrastructure
would maintain an acceptable degree of stability in the temperature.
Determination of the Effect of Interlayer Porosity on the Performance of Oxygen
Electrodes for Solid Oxide Electrolysis Cells. PATRICK
DRIEMEYER (University of Missouri
- Rolla, Rolla, MO, 65401) JENNIFER MAWDSLEY (Argonne National Laboratory, Argonne, IL, 60439)
Currently work
is being done on the thermochemical cycle known as the "Westinghouse
Process" in which hydrogen is produced. The step of interest
in the Westinghouse Process is the decomposition of SO3 to SO2
using electrolysis to lower the temperature at which this reaction
occurs. This step is considered a hybrid of thermochemical and
electrochemcical processes and reduces the highest temperature
of any step to 500-600°C from 850°C. The lower temperature range
opens the door for a wider array of materials to be used in construction
of a hydrogen production plant. The development of an oxygen
ion conducting cathode for the electrolyzer cell which exhibits
low resistance is desired since it would allow free exchange
of oxygen and electrons, thereby improving the performance and
output of the electrolyzer cell. The production and testing of
various cathode compositions along with an examination into the
effect of porosity in the doped-ceria interlayer will be examined
and reported on. The compositions that will be tested include
La0.5Sr0.5CoO3-d; Nd0.5Sr0.5CoO3-d; Ba0.5Sr0.5CoO3-d. These compositions
will be produced on site and tested in air within the temperature
range of 900°C to 500°C. Their performance will be measured using
electrochemical impedance spectroscopy (EIS) in which the area
specific resistance (ASR) will be calculated and compared to
determine the most appropriate design path. We have found that
the incorporation of porosity in the doped-ceria interlayer between
the oxygen electrode and the stabilized-zirconia electrolyte
improves performance.
Determining the Effect of Aerosol Composition on the Accuracy of Aethalometer
Real-Time Measurements of Black Carbon. SRYAN
RANGANATH (University of California, Berkeley, Berkeley, CA, 94709)
THOMAS W. KIRCHSTETTER (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
Black carbon
(BC), a main component of soot, is studied for its associated
climatic and health effects. Filter-based light-transmission
instruments are commonly used for measuring properties of black
carbon. The aethalometer performs real-time measurements of black
carbon concentration. Previous studies indicate that measurements
produced by light transmission instruments, and the aethalometer
specifically, are affected by the enhancement in particle light
absorption due to the light scattering within the filters used
to collect the particles. While the extent of this enhancement
varies with particle loading and particle composition, the aethalometer
algorithm does not consider these effects. This result could
jeopardize the quality of measurements of BC concentration made
with the aethalometer. This behavior was studied in the laboratory
using controlled generation of BC and light scattering aerosols.
An inverted diffusion flame produced BC aerosols with steady
physical characteristics. A nebulizer produced salt particles
which were mixed with BC from the flame. These particles were
diluted with filtered air prior to sampling. The aethalometer
sampled pure BC aerosols and BC + NaCl in individual experiments.
In both cases, the aethalometer reported a decreasing concentration
despite sampling a constant BC concentration. However, different
decreasing trends in concentration were observed, depending on
the composition of the aerosols sampled. This difference in instrument
response means that different empirical corrections are required,
which is not a practical solution to the problem. Continued investigation
with aerosols of different composition is the next expected step.
These results may be first steps in showing an empirical correction
for the aethalometer is not practical.
Development of a Long Ion Chamber Electrometer for Particle Accelerator Beam
Containment. NICHOLAS PATE (Tennessee Technological
University, Cookeville, TN, 38505)
PAUL WRIGHT (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
A common problem
in cavity-coupled linear particle accelerators is misalignment
of cavity phases resulting in particle beam loss over a short
distance; when an intense beam is lost in this manner, high levels
of ionizing radiation are developed that can pose a danger to
both personnel and the machine itself. Long Ion Chambers (LIONs)
provide a low-cost and -complexity method of monitoring radiation
levels along a length such as an accelerator, potentially allowing
a control system to take beam containment measures if a radiation
threshold is exceeded. LION implementation in machine protection
systems at the Spallation Neutron Source (SNS) requires that
a standard electrometer design be developed, validated, and calibrated
against other beam-loss and radiation detector systems. Circuit
analysis of an existing prototype electrometer was performed
to determine ideal characteristics of the design, and an experimental
frequency analysis was performed to verify suitability for use
under the expected measurement conditions. Because a vital piece
of measurement equipment was unavailable, it was not possible
to conduct a more detailed characterization of the circuit. It
was determined that the maximum input signal before output clipping
occurs is an order of magnitude higher than necessary, that gain
drops off significantly for signals above 10KHz, and that the
circuit operates as expected for relatively high input and offset
currents. Further work will include a more detailed spectrum
analysis, especially for small signals, determination of signal-to-noise
ratio, and investigation of a small interference source that
was observed during testing. This work is part of an ongoing
effort to evaluate and implement LION-based radiation monitoring
and beam containment in the SNS accelerator system.
Development of a Multi-Pollutant Personal Sampler (MPPS). MARIA
MINJARES (Our Lady of the Lake University, San
Antonio, TX, 78207) LARA GUNDEL (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
The effects
of indoor and outdoor air pollutants on human health have long
been a concern to health care workers, environmental scientists,
and citizens alike. Previous work has consisted of developing
methods for separating and trapping particulate matter (PM) and
gaseous pollutants. Currently, the multi-pollutant personal sampler
(MPPS) consists of denuder with polyurethane foam coated with
a ground sorbent, XAD-4, followed by a filter to collect PM < 2.5 µm
diameters (PM2.5). Indoor and outdoor air sampling was conducted
at Lawrence Berkeley National Laboratory to determine how much
PM2.5 the polyurethane foam would retain. The results obtained
from sampling indoor ambient air proves our hypothesis that the
PM2.5 will pass through the 80 pores per linear inch (ppi) XAD-4
coated PUF. However, the 80 ppi XAD-coated PUF retained 30% of
PM2.5 in its structure during outdoor air sampling. Further experimentation
is needed to improve the MPPS geometry so that > 95% of PM2.5
passes through the XAD-coated PUF to the filter.
Development of a One-Dimensional Coal Gasifier Model Using Fortran and UNIX. ANDREW ELDER (Gonzaga University, Spokane, WA, 99258) KEN JOHNSON (Pacific Northwest National Laboratory, Richland, WA, 99352)
Coal gasification
is a technique that is gaining attention as a clean fuel source
for highly efficient power plants that are also environmentally
friendly. In this process, coal is mixed with steam and a controlled
amount of oxygen while under high temperatures and pressures.
This environment causes the coal to break down into a synthesis
gas (i.e. syngas) of hydrogen and carbon monoxide with lesser
amounts of other gaseous compounds. The syngas can be used for
fuel, while the waste gases can be removed easily. The goal of
this project was to develop a one-dimensional computer model
that would predict the heat transfer through the outer wall of
the gasifier. (A one-dimensional model is one that deals with
heat transfer solely in a linear fashion). Using the Fortran
programming language on a UNIX machine, knowledge of conductive
heat transfer and an explicit forward difference numerical method,
two such one-dimensional models were developed. These models
determined the heat loss through the gasifier wall and the temperature
at various points through the wall. These models will serve as
the foundation for future work in coal gasification modeling.
Development of a System to Test Internal Pressurizer Dynamics. IRENE
BERRY (Virginia Polytechnic Institute and State University, Blacksburg, VA, 24060)
EMILIAN POPOV (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
The International
Reactor Innovative & Secure (IRIS) is a next generation pressurized
water reactor (PWR) that utilizes an integral coolant loop. The
coolant loop is inside the reactor vessel; the loop pressurizer
is in the upper head of the vessel and has larger liquid surface
area and volume than traditional PWR pressurizers. Because of
this, the internal pressurizer will respond differently to changes
in coolant volume and level. Its response to these dynamics must
be tested and characterized to optimize IRIS design and control.
A facility is being built at Oak Ridge National Laboratory to
test internal pressurizer dynamics. This project focused on preparing
the facility for operation and involved the completion of three
main tasks: designing the facility’s detailed layout and instrument
placements, developing operating procedures, and creating a Supervisory
Control and Data Acquisition (SCADA) system. To aid in designing
facility layout, a 3d model of the facility was created using
AC3D design software. This model was used to determine instrument
placements and pipe dimensions. Facility constraints and test
requirements posed many concerns that had to be addressed in
the operating procedures. To develop these procedures, facility
geometry and conditions, including temperature, pressure, coolant
density, and liquid level, were analyzed at start-up, operating,
and test states. Methods were then developed to safely and consistently
bring the facility to pre-test conditions, run tests, and shutdown
the facility. These procedures were automated as part of SCADA
system design. The SCADA system developed monitors the facility
and automates all start-up and test procedures. It was created
using Intellution FIX, an industrial automation software, and
consists of over 100 database blocks and five control panels.
These panels display instrument readings and allow the user to
enter set points and commands. A simple numerical model of the
facility was also created for use with TRAC/RELAP Advanced Computational
Engine (TRACE). TRACE is a computer code designed to model and
evaluate thermal and hydraulic transients in nuclear reactors.
The model developed will be used to approximate start-up and
test procedures and predict facility response. As a direct result
of this project, the internal pressurizer dynamics test facility
is nearing completion. Tests will begin as soon as all equipment
is assembled.
Digital Lock-In Amplifier Based Ground Loop Monitoring System for Magnetically
Confined Plasma Devices. EDWARD CAMP (University
of Hartford, West Hartford, CT,
6117) HANS SCHNEIDER (Princeton Plasma Physics Laboratory, Princeton, NJ, 8543)
A Ground Fault
Monitor (GFM) system currently in use for the National Spherical
Tokamak Experiment (NSTX) utilizes analog lock-in amplifier hardware
to monitor vacuum vessel grounds to detect and help prevent current
loops that are potentially dangerous to personnel and equipment.
A ground loop fault is a condition where a loop is created between
two single point grounds, potentially resulting in some level
of current flow. Previous research has shown that a digital lock-in
amplifier would improve the performance and operability of the
current system. An automatic gain control system that uses multiple
level transmit signals could improve detection of both low and
high impedance faults, rather than compromising on a single transmit
level that would be clipped at low impedance faults and be buried
in noise at high impedance. This gain control program, along
with a digital lock-in amplifier, both created in LabVIEW, an
integrated visual programming language, produced an increase
in usable sensitivity from 250 ohms to 50,000 ohms in the current
analog system to 2 ohms up to 70,000 ohms within 10% accuracy
and up to 150,000 within 25% error in the LabVIEW program. This
does not take into account false alarms and nuisance trips, only
the accuracy of the device at quantifying loop faults. Improvements
to this program could be implemented by adding moving average
filtering to improve calibration data and increasing the number
of discrete transmission levels used by the program.
Digital Voltage Controller for the Field Emission Microscope at Jefferson Lab. BRENDAN MATHEWS (West Virginia University, Morgantown,
WV, 26506) JOHN MUSSON (Thomas Jefferson National Accelerator
Facility, Newport News, VA, 23606)
Jefferson Lab
(JLab) uses refined niobium to create superconducting cavities
for the electron beam. Several polishing procedures are used
on the niobium to ensure that arcing does not occur inside these
cavities due to inconsistencies on the surface of the cavities.
The metal is examined under a field emission microscope to detect
any remaining flaws on the surface. This microscope runs a steady
current between the niobium and a phosphorous screen and measures
the voltage changes in order to detect and stalagmites that may
appear on the metal. This device requires that the voltage in
the system be regulated in order to maintain a steady current.
Until recently this device was manually controlled, but the ultimate
goal of this project was to create a device that would eliminate
this unnecessary human error. This new device would require analog
inputs so an analog to digital converter (ADC) was necessary
to allow manipulation of the inputs. After the data comes in
through the ADC, it was processed by an infinite impulse response
filter in an attempt to eliminate any noise. After this process
is completed, the date is fed into a proportional integral derivative
controller in order to bring the output to the desired level.
Finally, after all of this is completed the signal is fed back
out into the system by way of a digital to analog converter (DAC).
Testing has shown that the controller is able to maintain a steady
voltage level within 10% of the desired value. Automating this
process will allow JLab to have a more efficient procedure, as
well as provide for more accurate mapping of the niobium used
in the beam cavities.
Effect of neodymium oxide on thermal and mechanical properties of alkaline
earth sealing glass for solid oxide fuel cells. BRIAN
BISKIE (Northern Illinois University, DeKalb, IL, 60115) YEONG-SHYUNG CHOU (Pacific Northwest National Laboratory, Richland, WA, 99352)
Earlier work
on glass seals for solid oxide fuel cells (SOFCs) has shown that
when fuel cells are operated over long periods, glass seals tend
to react with the ferritic stainless steel interconnects at the
metal/glass interfaces, and form undesirable phases. An approach
for this problem was to make sealing glasses more refractory
such that the glass would be sealed at higher temperatures (i.e.,
950°C) and thus be less reactive at operational temperatures
of (750-800°C). In this study, a novel glass series containing
Sr-CaO-Nd2O3-B2O3-SiO2 was
developed to determine the effect of Nd2O3 on the thermal and mechanical properties of the glass. Properties
such as coefficient of thermal expansion (CTE), glass transition
temperature, softening temperature, and elastic modulus were
determined as the neodymium content was varied throughout the
glass series. The results showed CTE increased with increasing
Nd2O3 content up to 5 mole percent which had a CTE of 11.97 ppm/°C
for as-cast glass, while the glass transition and softening points
showed different behaviors. A similar alkaline earth silicate
glass was used for interfacial strength testing. In addition
to as-sealed coupons, samples were also aged in either air or
a reducing environment to study the environmental effect on interfacial
strength. The results showed the tensile strength decreased ~53%
when aged in air at 850°C for 250 hours, and increased ~38% when
aged 250 hours at 850°C in moist, dilute hydrogen fuel. Possible
causes for the strength change were discussed.
Effect of Reactant Gases Humidification on Hydrogen
Fuel Cell Performance. FIDA
ABDULLAH (State University of New York at Farmingdale, Farmingdale,
NY, 11706) DR. DEVINDER MAHAJAN (Brookhaven National Laboratory,
Upton, NY, 11973)
Recent experimental
investigations on polymer electrolyte membranes (PEM) fuel cells
emphasize water management as being a critical factor in the
design of an efficient cell. The current research project aims
to explore the influence of humidified air and hydrogen on the
fuel cell’s performance. The first part of this experimental
work was conducted on a five graphite bipolar plates fuel cell
power stack, while operated under various loads, and involved
the measurement of dry reactant gases (hydrogen and oxygen/air)
humidity and temperature entering and exiting the fuel cell.
The results, obtained at room temperature, indicated a substantial
increase in the exiting humidity of oxygen (25.26%) despite the
humidity entering the cell being relatively constant at 50% RH.
The air exiting the cell plateaus at 75.15% RH (relative humidity).
A comparison of the effect of both hydrogen and oxygen/air gases,
under similar conditions, on the power stack performance was
made. The oxygen’s substantial increase in humidity was matched
by a smaller increase (14.3%) from the exiting hydrogen side.
when dry gases were used the power stack yielded a maximum power
density of 19.43 mW/cm² and a maximum current density of 41.33
mA/cm². The second part of the experiment involved conventional
methods of external-humidification of the oxygen gas/air and
the humidified air entering the cell was changed in a range from
85.63% to 78.42% RH. As a result, the humidified air exiting
the cell yielded a slight increase in humidity to 2.11%. Comparing
humidified air versus non-humidified air a 72.77% increase in
power density was observed. Since the results in the dry cell
(no humidification) yielded a slight change (14.3%) in the exiting
hydrogen humidity, the consequent step was to humidify circulating
hydrogen and the results yielded a slighter gain of 12.87% (21.93mW/cm²)
in power density. The final part of the experiment was the humidification
of both reactant gases. The entering humidification of both gases
yielded less improvement in performance than the previous scenarios,
when each reactant gas was humidified one at a time. Also, when
both entering reactant gases were humidified the exiting hydrogen
humidity increased by 2.1% and the exiting air humidity increased
by 11%. Initially, the humidification of both reactant gases
yielded better performance than solely humidifying hydrogen but
fell short of the performance of solely humidifying air. Humidification
of air showed a maximum power density increased by 54.24%, and
proved to be more influential than humidifying hydrogen or both
gases.
Electrical Properties of Materials with a High Dielectric
Constant. CHRISTOPHER DIXON (University of Delaware, Newark, DE, 19713) STEVE HULBERT (Brookhaven National Laboratory, Upton, NY, 11973)
Silicon integrated
circuits are based on the Metal-Oxide Semiconductor Field Effect
Transistor (MOSFET). A MOSFET uses a layer of oxide (an insulator)
sandwiched between a layer of metal (gate) and a semiconductor
to control the flow of electrons between the source and drain.
The goal of creating a transistor using high-k dielectrics is
to achieve a smaller transistor so that more transistors can
be packed into a smaller area. As transistors get small, the
leakage current across the dielectric increases leading to problems
with battery lifetime and heat dissipation. Thus, new materials
are being investigated for use as gate insulators in order to
decrease the leakage current. In older electronics the gate electrode
is usually a polysilicon semiconductor. Metal gates are desirable
to use because they help to limit reaction at the gate/dielectric
interface. The energy levels of different metals relative to
the energy levels of the high k dielectrics determines the leakage
current through the dielectric. Samples of the dielectric,(HfO2)x(SiO2)1-x
were analyzed by using ultraviolet photoelectron spectroscopy(UPS).
UPS is a technique for measuring the energy spectrum of electrons
emitted during the absorption of ultraviolet radiation. The relative
alignment of the energy levels of the Si substrate, the dielectric
film, and the gate electrode will determine the electrical properties
of the transistor. This spectrum reveals the characteristic ionization
energies of the component atoms and facilitates study of their
chemical nature. Utilizing UPS it is possible to see the Fermi
level and energy levels of the materials that are being considered.
Analyses were run on the samples with different amounts of Ag
and Alevaporated onto the surface of the dielectric samples.
Data was recorded as a function of metal thickness for both Ag
and Al depositions.The Secondary Electron Cutoff (SEC) made it
possible to determine the work function of the samples being
tested, and to discover whether any electric charge was transferred
at the metal/insulator interface. The threshold voltage (and
consequently the drain to source on-current) is determined by
the work function difference between the gate material and channel
material. Measurements we are undertaking will help determine
which metal and dielectric are used in future generations of
very highly integrated circuits.
Electrochemical Characteristics of Composites Containing (x)LiNi0.5Mn0.5O2 • (1
- x)LiNi0.5Mn1.5O4 as the Active Material in the Cathode. JONATHAN
BREITZER (Fayetteville State University, Fayetteville, NC, 20835)
CHRISTOPHER JOHNSON (Argonne National Laboratory, Argonne, IL, 60439)
Our FaST team
from Fayetteville State University, a constituent institution
of the University of North Carolina, synthesized and evaluated
cathode materials for use in high-energy lithium-ion batteries.
These cathode materials were composites of lithium nickel manganese
oxides in different stoichiometric ratios that adopt either a
spinel or an ordered rocksalt structure. Working in conjunction
with CMT scientist Dr. Christopher Johnson, this team functioned
well in generating useful data, dividing the labor by mutual
agreement. Over the course of this research, the team was introduced
to a wide variety of other summer researchers and regular employees
of Argonne National Laboratory, and was educated in many ways
about the safety culture of the Laboratory. The results of our
research were useful in guiding the direction of further inquiry,
and the experience we gained from the FaST program has led us
to desire further collaboration. This will advance research in
a critical field, promote our University through grant-writing
activities, and provide a valuable opportunity to more undergraduate
students.
Enhancement of Airside Heat Transfer in Air-Cooled Condensers for Binary Cycle
Geothermal Power Production. CHRISTOPHER
HANNEMANN (University of California, Berkeley, Berkeley, CA, 94720) CHUCK KUTSCHER (National Renewable Energy Laboratory, Golden,
CO, 89401)
Binary cycle
geothermal power production requires a majority of the thermal
energy in the working fluid to be rejected after exiting the
turbine. Because abundant sources of cool water are not available
near many of these geothermal wells, air-cooled condensers must
be used instead of the preferred water-cooled systems. The capital
cost for these condenser arrays, as well as the parasitic power
consumed to run the required fans, contributes significantly
to the total cost of geothermal power. To improve the airside
heat transfer in these condensers, enhanced fins are being tested
at the National Renewable Energy Laboratory; slit and bent annular
fins are examined in the present study. Transient testing is
performed on small tube sections to determine performance improvements
based on heat transfer coefficients and pressure drops as well
as to select an optimum bending angle. Using the results from
the transient tests, a steady-state test using a 17 tube, single
pass cross flow heat exchanger is performed. The slit fins are
tested unbent and bent at 12° in two different configurations,
using water as the working fluid and testing each sample at four
different air flow rates. The “staggered” arrangement is shown
to perform the best, and the 12° bent fins are shown to outperform
the unbent fins by 3 – 5% heat transfer per unit hydraulic power.
Both the unbent and bent fins underperform model predictions,
possibly due to corrosion within the tubes. Further work will
focus on retesting the bent slit fins with the corrosion removed
as well as examining the effects of twisting the slit fins.
Enhancing the Target Chamber for the Second Phase of the Neutralized Drift
Compression Experiment. GUILLERMO GARCIA (University
of Southern California, Los Angeles, CA, 90089)
MATTHAEUS LEITNER (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
The objective
of a controlled fusion power plant for worldwide energy production
has driven the Neutralized Drift Compression Experiment (NDCX)
to investigate characteristics of ion-beam manipulation. This
report focuses on enhancing the diagnostic target chamber for
the second phase of the NDCX project. A target capsule, loading
dock, robotic arm and target housing were developed to prepare
the diagnostic target chamber for integrated compression and
focusing experiments with energy transfer of 1 eV on target with
a 500 MW, 1 ns ion beam. Each component was developed to incorporate
the design constraints established by the diagnostic target chamber.
A LabVIEW program was created to monitor and control movement
of the robotic arm. The diagnostic target chamber was assembled
and calibration of the robotic arm showed that the system had
successful interaction between the LabVIEW program and the newly
developed components.
Evaluation of a 4.5 kW Air-Cooled Lithium Bromide/water Solar Powered (Hot
Water-Fired) Absorption Unit. DAVID GOODNACK (Pennsylvania
State University, University Park, PA, 16802) ABDOLREZA ZALTASH
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
During the
summer months, air-conditioning (cooling) is the single largest
use of electricity in both residential and commercial buildings
with the major impact on peak electric demand. Improved air-conditioning
technology has by far the greatest potential impact on the electric
industry compared to any other technology that uses electricity.
Thermally activated absorption air-conditioning (absorption chillers)
can provide overall peak load reduction and electric grid relief
for summer peak demand. This innovative absorption technology
is based on integrated rotating heat exchangers to enhance heat
and mass transfer resulting in a potential reduction of size,
cost, and weight of the "next generation" absorption
units. Rotartica Absorption Chiller (RAC) is a 4.5 kW air-cooled
lithium bromide (LiBr)/water unit powered by hot water generated
using the solar energy and/or waste heat. Typically LiBr/water
absorption chillers are water-cooled units which use a cooling
tower to reject heat. Cooling towers require a large amount of
space, increase start-up and maintenance costs. However, RAC
is an air-cooled absorption chiller (no cooling tower). The purpose
of this evaluation is to verify RAC performance by comparing
the Coefficient of Performance (COP or ratio of cooling capacity
to energy input) and the cooling capacity results with those
of the manufacturer. The performance of the RAC was tested at
Oak Ridge National Laboratory (ORNL) in a controlled environment
at various hot and chilled water flow rates, air handler flow
rates, and ambient temperatures. Temperature probes, mass flow
meters, rotational speed measuring device, pressure transducers,
and a web camera mounted inside the unit were used to monitor
the RAC via a web control-based data acquisition system using
Automated Logic Controller (ALC). Results showed a COP of approximately
0.58 at 35°C design condition for ambient temperature with 40°C
cooling water temperature and approximately 3.7 kW capacity.
This is in close agreement with the manufacturer data of 0.60
for COP and 3.9 kW capacity. This study resulted in a complete
performance map of RAC which will be used to evaluate the potential
benefits of rotating heat exchangers in making the "next-generation" absorption
chillers more compact and cost effective without any significant
degradation in the performance. In addition, the feasibility
of using rotating heat exchangers in other applications will
be evaluated.
Evaluation of Long-Term Brake Performance Using Performance-Based Brake Testers
(PBBT). JESSICA JOSEPH (Southern
University A&M of Baton Rouge, Baton Rouge, LA, 70816)
GARY J. CAPPS (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Performance-Based
Brake Testers (PBBTs) are devices that can evaluate the current
braking capabilities of a vehicle through the measurement of
brake forces developed as a vehicle engages in a braking event
while on a PBBT. They are widely used for brake inspection in
Europe and Australia and are beginning to emerge as both an enforcement
tool and diagnostic aid for private sector maintenance and repair
shops. Because of the significant benefits of utilizing PBBT
technologies (time/labor savings, error reduction, objective
measures, consistency, enhanced fleet safety), Federal Motor
Carrier Safety Administration (FMCSA) has an interest in assessing
a vehicle’s long-term brake performance using PBBT technology
over time in a real-world testing environment. This will be done
in conjunction with volunteer fleets (including a motor-coach),
over a sufficiently long period of time, to measure (for each
vehicle in the test fleet) the brake force for the overall vehicle,
and for each individual wheel-end. Such an effort would provide
experiential data, and would quantitatively assess benefits from
long-term brake performance data. A market search was done to
find manufactures or sole distributors of PBBT devices that offer
artificial axle loading (AAL) capability and research was done
to understand the theory of operation of the PBBT. The different
types of PBBT (roller, in-ground, portable) were evaluated to
decide which PBBT with AAL would be best for research based on
meeting FMCSA’s Functional Specifications. An evaluation was
completed for three possible vendors to determine which vendor
would provide the best PBBT for research applications and a training
module for use by the Tennessee Department of Safety Personnel.
The vendor’s PBBT must be certified and meet the FMCSA criteria
in order to be a candidate to provide a PBBT. A survey and location
matrix was done to compare and decide which one of three possible
locations would accommodate the needs for the State of Tennessee
and Oak Ridge National Lab.
Evaluation of Various New Anode and Cathode Materials for High Power Li-Ion Battery
Applications. STEPHANIE
TRAN (Michigan State University, East Lansing, MI, 48823)
JUN LIU (Argonne National Laboratory, Argonne, IL, 60439)
Since the establishment
of the Partnership for a New Generation of Vehicles Program (PNGV)
between the US government and the US Council for Automotive Research
in 1993, much research has been invested into developing more
efficient high power and high energy density hybrid electric
vehicles (HEV). The power and performance properties of a Li-ion
battery system make it an efficient source of energy for the
automobile. However, high production costs of the Li-ion battery
make them difficult to be accepted by automobile manufacturers.
LiMn2O4 Spinel and LiFePO4 Olivine active cathode materials are
cheaper to produce and may still maintain the performance characteristics
of the Li-ion system. Cycling performance tests for these materials
have shown a stable battery capacity over many charge-discharge
cycles in room temperature and high temperature conditions. Potential
hard carbon anode materials also display the prevention of capacity
loss at elevated temperatures and long term battery usage. Cost
efficient battery components that can still uphold the high power
and high energy qualities of a lithium-ion battery system are
promising to the new generation of hybrid vehicles.
Examining the River Water and Groundwater Interface in a Hyporheic Zone Mesocosm. CAROLINE NEWCOMBE (Arizona State University, Tempe, AZ, 85287)
DR. AMORET BUNN (Pacific Northwest National Laboratory, Richland, WA, 99352)
The hyporheic
zone of a river or stream is the area of the streambed where
groundwater and surface water mix. It is an important area of
study because it is an integral part of the river ecosystem with
unique physical, chemical, and biological characteristics. This
paper will discuss the initial steps in the design and construction
of a hyporheic zone mesocosm under development at Pacific Northwest
National Laboratory (PNNL). An enclosed experimental ecosystem,
called a mesocosm, is well-suited for investigation of the hyporheic
zone because it provides control and repeatability in the experiment.
A unique feature of the hyporheic zone mesocosm under development
at PNNL is that it incorporates both river water and groundwater
flows into the sediment profile, whereas previous studies have
only examined the effects of influent river water or influent
groundwater. Since this mesocosm is using a novel approach in
incorporating two types of water, it was necessary to investigate
practical designs for sampling ports in the system, as well as
to identify appropriate parameters for determining the distribution
of groundwater and river water in the system. The hyporheic zone
mesocosm consists of a sediment profile contained in a larger,
insulated tank. Different configurations of sampling ports were
tested by making rectangular or circular cuts in rigid high-density
polyethylene tubing. Several water quality parameters of river
water and groundwater were also tested in order to determine
the best method to characterize the mixing of river water and
groundwater within the completed mesocosm. The type of sampling
port selected was a series of three 2 mm x 2 mm square cuts spread
across a 5 cm length in the center of the tube. Testing several
different water quality parameters showed that conductivity is
the most reliable way to measure the extent of the river water
and groundwater mixing in the hyporheic zone mesocosm, and further
testing ensured that conductivity would not increase as a result
of salts leaching from the sediment into the water. However,
conductivity does not directly relate to uranium speciation or
water quality for biological growth, so water quality parameters
such as alkalinity, dissolved oxygen, hardness, pH, and ORP will
have to be monitored as well.
Exhaust Gas Recirculation Effects on Diesel Engine Soot Formation, Destruction,
and Emissions. EDWIN HUESTIS (University
of California, Davis, Davis, CA, 95616) MARK P. B. MUSCULUS (Sandia National Laboratory (California), Albuquerque, NM, 87185)
Diesel engine
manufacturers desire insight into the internal processes that
affect emissions in order to design new engines that meet upcoming
US pollutant emissions regulations for particulate matter (soot)
and nitrogen oxides (NOx). Exhaust gas recirculation (EGR) is
one available tool to reduce pollutant emissions of NOx, and
EGR has also been shown to reduce the formation of soot in fundamental
combustion studies. In real engines, however, EGR can increase
soot in the engine exhaust by affecting soot destruction processes
after combustion. In this study, both exhaust-gas soot emissions
and fundamental soot formation/destruction processes inside a
diesel engine are measured to understand how these processes
affect the ultimate soot emissions. The time-evolution of soot
formation and destruction inside an optically accessible diesel
engine is measured by analyzing the radiative emission spectrum
of the combustion-heated soot. The soot radiative emission intensity
is measured within two separate spectral bands, and along with
high-speed luminosity movies, the soot temperature and concentration
inside the engine are determined using the two-color soot thermometry
technique. Gases are also sampled from the exhaust stream and
drawn through a filter to collect the soot particles for exhaust-gas
measurements. The measurements show that soot formation inside
the engine decreased as EGR was added, but soot destruction processes
decreased more rapidly, so that exhaust soot emissions increased
as EGR was added. Only at very high EGR levels did the exhaust
soot emissions decrease, as the soot formation processes became
very slow. Finally, soot temperature measurements show that the
reaction rates for soot formation and destruction depend on EGR,
affecting the soot formation/destruction balance. By combining
measurements inside the engine with exhaust-gas measurements,
the effects of EGR on the soot formation/destruction balance
were quantified in a single experimental facility. The data from
this study shows that EGR decreases soot destruction processes
more than soot formation processes, so that the balance is tipped
toward higher exhaust soot. At very high EGR, however, soot formation
processes are so slow that exhaust soot decreases, even with
reduced rates of soot production. This study also identifies
the tipping points where this balance shifts from increasing
exhaust soot to decreasing exhaust soot.
Experimental Test of Relaxational Attenuation for Carbon Dioxide. ANGEL SANTIAGO (University of Massachusetts, Amherst, Amherst, MA,
1003) MORRIS GOOD (Pacific Northwest National Laboratory, Richland, WA, 99352)
Attenuation
is the reduction of intensity of an ultrasonic wave. Relaxational
attenuation occurs when excited molecules do not exchange vibrational
or rotational energy infinitely fast with translational waves.
The purpose of this research is to determine relaxational attenuation
can be shown experimentally. Attenuation is frequency dependent.
The study of ultrasonic propagation in CO2 was studied at 3 atmospheres
in varying frequencies. The experiment was carried out using
a modified pressure chamber made from a commercial paint can.
Data was collected through an oscilloscope for various transducer
spacing at increments of a tenth of an inch, in order to facilitate
attaining the attenuation of varies frequencies. All data was
analyzed using Microsoft Excel and Mat lab software. Plotting
the data for attenuation due to frequency I was able to match
the CO2 experimental graph and the theoretical graph. The experiment
has shown the ability to obtain the relaxation attenuation of
a gas. More experiments are needed with other gases to show working
with the relaxation attenuation of a gas would be of practical
use as an identifier of specific gases.
Heavy Truck Duty Cycle Study. MARY LASCURAIN
(Pensacola Christian College, Pensacola, FL, 32503)
GARY CAPPS (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
To date, little
real-world scientific data regarding long-haul, Class-8 tractors
and their engine and drive train components has been collected
for analysis. Of great importance to the study of this class
of commercial vehicle is the understanding of how factors such
as tire type and vehicle loading influence fuel efficiency. Because
many variables cannot be controlled in real-world data collection,
simultaneous monitoring of these variables such as weather conditions
and road topography can aid in the production of useful data
that can be analyzed to isolate controllable variables which
influence vehicle efficiency (i.e. tire rolling resistance).
Building on efficiency-related data available directly from the
truck’s J1939 controller area network (CAN), an eDAQ Lite data
acquisition system (DAS) was assembled to integrate several external
sensors. Data from these sensors augment the duty cycle data
by providing not only GPS-based information such as speed and
acceleration, but also weather conditions, road topography, and
weight information to increase understanding of long-haul operations.
In the absence of a Class-8 truck for the earliest stages of
testing, several DAS units were placed on passenger cars to collect
data in normal operation for up to a week at a time. These tests,
which reflected extended periods of real-world driving conditions,
more closely simulated the ultimate (long-haul) application of
the systems than previous bench-top testing. The results from
these tests showed a discrepancy between the tilt sensor data
and actual road grade. Preliminary testing also provided readings
for speed and wind, which were found to differ significantly
from one another. Analysis of the test data revealed that the
tilt sensor readings not only were influenced by the natural
vibrations of the vehicle, but also responded dramatically to
vehicle tilt caused by acceleration and deceleration. Further
testing will be conducted to verify that sufficient GPS altitude
data can be collected to make the inclusion of a tilt sensor
unnecessary. A comparison between wind and speed readings indicated
that the weather station provides a sufficient indication of
headwind. When a class-8 truck becomes available for instrumentation,
the truck database will be integrated into the existing DAS for
final testing of the system; these systems will then be installed
in five to six trucks in a commercial fleet to gather data for
a twelve-month study of heavy truck duty cycles.
Hydrolysis Reaction of the Copper-Chloride Thermochemical Cycle in a Vertical
Reactor. DAVID TAGLER (University of Notre Dame, Notre Dame, IN, 46556) MICHELE A. LEWIS (Argonne National Laboratory, Argonne, IL, 60439)
Thermochemical
cycles have been developed to produce hydrogen at competitive
energy efficiency levels while generating low greenhouse gas
emissions. The copper-chlorine (Cu-Cl) thermochemical cycle is
designed to split water and produce hydrogen at the relatively
low peak temperature of 550° C. This cycle consists of three
thermal reactions and one electrochemical reaction. This project
is concerned with one of the thermal reactions, the thermal hydrolysis
reaction of cupric chloride, CuCl2,
from 350° C to 400° C at atmospheric pressure. The reaction is
2CuCl2 (s)
+ H2O
(g) Cu2OCl2 (s)
+ 2HCl (g). The goal of this experiment is to determine the optimum
operating conditions (temperature, flowrate, steam ratio, and
reaction time) to maximize the desired products, Cu2OCl2 and HCl, while minimizing the products of any competing reactions.
Argon gas at 100-200 ccm is used to transport steam through a
15 inch vertical reactor containing 150-500 mg of solid CuCl2 in
a crucible with a 13 mm ID (inside-diameter) crucible for 15-60
minutes. HCl is collected in a condenser container and water
trap. X-ray diffraction (XRD) is used to analyze the solid products
of the reaction and determine purity. XRD analysis shows that
a competing decomposition reaction of CuCl2 to
CuCl increases at temperatures greater than 350°C. The optimum
temperature was found to be between 350°C and 375°C for 500 mg,
and the optimum reaction time was found to be between 30 and
60 minutes. Greater sample surface area also proved to decrease
the amount of CuCl produced. Thus, this experiment was successful
in optimizing this reaction. Future studies need to look deeper
into the effect of surface area, flowrate, temperature, and reaction
time in order to further optimize this reaction.
Increasing the Durability and Reliability of Radiation Detectors used in Radiopharmaceutical
Chemistry. SIMARJIT
KAUR (Contra Costa College, San
Pablo, CA, 94806) JAMES P O'NEIL (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
Radiation Detectors
are a necessary part of radiopharmaceutical synthesis in order
to determine the quantity of radioactivity throughout the synthesis.
They are used to track not only the progress of the chemical
reactions and the yield at each step but also to ensure the safety
of the personnel involved in this process. Radiation detectors
are usually installed in places where the potential of chemical
exposure and general physical abuse is quite high. To make the
radiation detectors more robust and reliable, a very easy and
cost-effective method of “epoxy potting” was devised. The radiation
detector is placed in a mold of appropriate dimensions and filled
with epoxy (3M Scotch-Weld DP270, black). After the epoxy cures,
the radiation detector is protected within a solid light resistant
block. This particular epoxy was chosen for this task because
it is chemically inert and provides both electrical and mechanical
insulation of the detector components from the harsh surroundings
of the hot cell.
Increasing X-Ray Brightness From 3rd Generation Light Sources: Design Study
of an Advanced In-Vacuum Magnet Gap Separation Mechanism for
Cryogenic Permanent Magnet Undulators and Superconducting Undulators. KOBBINA
AWUAH (State University of New York at Binghamton, Binghamton,
NY, 13902) JOHN SKARITKA (Brookhaven National Laboratory, Upton,
NY, 11973)
In recent years,
superconducting undulators (SCU) and cryogenic permanent magnet
undulators (CPMU) have been implemented in synchrotron radiation
facilities in order to obtain brighter beams. Due to increasing
project costs, there have been recent attempts to improve upon
the versatility of the undulator design. Consequently, a chamber
that can house either a CPMU or an SCU was designed to help reduce
project costs encountered when shifting from a CPMU to an SCU
and vice-versa. All models for the project were created using
INVENTOR software. Three meter segments of each kind of magnet:
superconducting magnet (SCM) and cryogenic permanent magnet (CPM)
were created. Since the SCM cannot operate under ultra-high vacuum
(UHV) conditions, it was placed in a vacuum-proof box before
inserted into the UHV chamber. In order to generate the required
magnetic field in an undulator, two magnets of the same kind
are aligned to have their poles facing each other and the field
is usually controlled by adjusting the gap between the two magnets.
Two different gap separation mechanisms (GSM) were studied: one
incorporated the use of wedges and rail bearings and the other
flexure bearings. The goal was to have a mechanism that could
adjust the gap between a 5-50mm range. During the studies, it
was found that flexure bearings have no backlash and no friction
during operation as compared to wedges and rail bearings. The
latter attribute of flexure bearings makes it ideal for use in
UHV environments since no oiling is required for the bearings
and this reduces outgassing in the UHV chamber. Also, flexure
bearings are relatively cheap and readily made. However, flexure
bearings tend to be inaccurate at larger gaps mainly because
the geometric center of the bearings tend to shift significantly
(up to 0.5mm) during large-angle operations (15 ). Since the
design could only accommodate a misalignment of the magnets in
the order of microns, the flexure bearing GSM was not implemented
in the final design. Instead, custom ceramic wedges and rail
bearing were used in the GSM to reduce friction and springs were
used to reduce backlash. Previous GSM models were usually placed
on the outside of the vacuum chamber resulting in complexity
and increase in project costs. The final design was able to achieve
an in-vacuum GSM using less complex components: wedges and rail
bearings driven by linear motors. This greatly reduced the overall
size of the undulator and also the cost involved.
Industrial Belt Inventory and Research. SCOTT
GERKEN (Montana Tech, Butte, MT, 59701) DALE SCHIELKE (Pacific Northwest National Laboratory, Richland, WA, 99352)
Throughout
the years at Battelle there has been a build up in machine equipment
and an inconvenient way of finding that equipment. The Millwrights
were complaining about how hard it was to find the exact belts
they needed. They would also take belts from other buildings
and forget to re-order replacements, leaving that building a
few belts short when those belts were needed. Inventory is a
serious problem for businesses. This problem has ramifications
for any essential part that can wear out. A system was needed
to keep inventory up to date on the belts. The system Battelle
has for keeping track of Battelle’s equipment is called "Maximo." After
putting every belt in the system and matching them to their machinery,
it allows anyone to get on and find out exactly where each belt
is. They will be capable of typing in the name of the machine
that needs new belts and Maximo will tell them exactly which
belt it needs, how many, and which buildings the selection of
belts are located. Other things capable of entering into Maximo
that are future possibilities include filters, shivs, and emergency
release valves. The dawn of Maximo has started a new beginning
to inventory for Battelle and its future audits.
Inner Reflector Plug Pipe Cutter for the Spallation Neutron Source. DAVID MACNAIR (Georgia Tech, Atlanta, GA, 30332)
CRAIG BRADLEY (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
The Spallation
Neutron Source (SNS) drives high velocity protons into liquid
mercury which will create the most powerful neutron scattering
source in the world. When the protons hit, the neutrons are ejected
and the mercury becomes radioactively activated which together
with the neutrons irradiate nearby equipment. The Inner Reflector
Plug (IRP) serves as a moderator and a heat sink for the mercury
target and nearby components. Water fed through pipes running
through the IRP absorbs the heat and transfers it to cooling
equipment. After about 2 to 5 years, the components of the IRP
become damaged due to intense gamma and neutron radiation. Removal
must be accomplished by disassembling each layer of shielding,
cutting the pipes that ran through that layer, and then repeating
for the next and subsequent layers. Methods for removing the
shield blocks have already been developed but the SNS needs a
pipe cutter. The cutting device must withstand the high radiation
environment, cut the pipes inside the IRP without leaving a mess
or deforming the pipes so as to make removal of subsequent layers
difficult, transport the pipes to a shielded cask, and be used
remotely. To reduce costs, not all components of the pipe cutter
were designed from scratch. The inner cutter housings, for example,
came from commercial tools and had to be analyzed and tested
to find the amount of torque required to cut through the IRP
pipes. All components were designed or modeled using the solid
modeler Pro/Engineer and then analyzed using hand calculations
and finite element analysis with Pro/Engineer Mechanica. Results
of the calculations were verified by the Remote Systems Group
of the Nuclear Science and Technology Division and the SNS Division,
and finally the design drawings were completed. Due to the inaccessibility
of the irradiated areas by humans during SNS operation, each
component inside these environments must be carefully designed,
analyzed, and tested before being put into use. Additionally,
components must be easily accessible, maintainable, and maneuverable
by remote handling equipment so that the SNS can continue its
mission of scientific discovery even beyond the length of its
original design.
Innovative Analysis and Decision Tools. MATTHEW
SIMON (University of Washington, Seattle, WA, 98195) HEATHER DILLON (Pacific Northwest National Laboratory, Richland, WA, 99352)
Decision makers
in the energy sector rely heavily on modeling and scenario planning
when making important decisions. These decisions could be related
to initial power plant designs, policies regarding global warming,
or new building code regulations, among others. Unfortunately,
the future is unpredictable. Uncertainties within the models
will undoubtedly cause failures in some real-world applications.
Despite the problems associated with these methods, these techniques
are heavily relied on to make important decisions in both design
and policy. Without the techniques of modeling and scenario planning,
making decisions would be extremely difficult, because there
would be no efficient way to analyze the different outcomes from
making one decision over another. Through several literature
reviews, many current modeling software tools and techniques
were examined. Each piece of software has its own strengths and
weaknesses when looking at robustness. Depending on the application,
some software tools are more appropriate than others. Of particular
interest was a set of new software tools designed for robust
analysis. These tools, developed by Evolving Logic, are the Computer-Assisted
Reasoning system (CARs) and the Robust Adaptive Planning (RAP)
software. Although they had not been extensively applied to many
energy related applications, they are a promising set of software
tools allowing for the analysis of problems dealing with deep
uncertainty, allowing analysts to make more robust decisions.
This paper looks at past and possible future applications of
these software tools and how they can improve the decision making
process.
Integrating Radiation and Radiofrequency Identification Portal to Monitor the
Movement of Radioactive Materials. NATHAN
ROWE (University of Tennessee, Knoxville, TN, 37996) CHRIS PICKETT (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Radio Frequency
Identification (RFID) is a fairly new technology that allows
for barcode type identification remotely over short distances.
There is an interest in using this technology for tracking nuclear
materials. One way of doing this is to use RFID portals at access
points between materials balance areas. The inclusion of a radiation
monitor to this portal would allow for a second level of confirmation
of the item being moved. Radiation Portal Monitors are already
in use to detect unauthorized movement of nuclear material. In
order to demonstrate the integration of an RFID portal with a
radiation portal, an RFID portal system was interfaced with an
existing radiation portal monitor. The radiation portal monitor
was connected to a local PC using a serial interface. Windows
services and web services were used to log the data from the
radiation portal into a remote database. The RFID web interface
is then able to use the database to compare the declared radiation
status of the item with its measured radiation level, and alarm
if they don’t match. The system shows the potential for integrating
other security systems with RFID, and shows promise for using
RFID for improved nuclear inventory management. Web services
make a good communications system to integrate security systems
of this type, because of its expandability and modularization.
A similar method could be used for combining other types of systems
with the RFID software as well.
Inventory using MAXIMO. MARCUS DE LA ROSA (Gonzaga
University, Spoakne, Wa, 99258) DALE SCHIELKE (Pacific Northwest
National Laboratory, Richland, WA, 99352)
Every building
at Pacific Northwest National Laboratory has a mechanical room
full of machines that provide hot and cold water, compressed
air, electricity, breathing air, and other services to the building.
A key component of this equipment are the belts that drive the
different machines. The main project that was accomplished this
summer was the categorization and inventory of these belts. Using
the standard numbering system, data was collected on all the
belts as well as the equipment the belts were used on. This data
was then implemented into our database Maximo. Now, when a belt
needs to be replaced it can be easily located and used, which
reduces the downtime of equipment.
Investigation of a Rhodium Catalyst in the Reduction of Carbon Dioxide and
Pyruvate for Future Use in a Direct Electrochemical Methanol
Production Cell. LINDSAY DIERCKS (University of Iowa, Iowa
City, IA, 52242) JOHN KERR (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
In a world
with dwindling oil reserves and increasing energy demands, reduction
of carbon dioxide to methanol using solar generated electricity
is a probable and environmentally conscious solution. The part
of the carbon dioxide to methanol process that this research
is specifically involved in is the reduction of carbon dioxide
to formate. The stereo-selectivity of Lactic Dehydrogenase (LDH)
was investigated in the reduction of pyruvate to lactic acid
as was the reduction of carbon dioxide to formate with only a
Rhodium catalyst. Reactions were run in a glass electrochemical
cell, and products of the reactions were analyzed on a Capillary
Electrophoresis (CE). The pyruvate reaction showed the presence
of lactic acid, however it was not certain if pyruvate was also
present. The absence of pyruvate on the CE analysis of the pyruvate
reaction could mean that there was a one hundred percent conversion
of pyruvate to lactic acid, but that result has yet to be reproduced.
The carbon dioxide reaction shows the presence of formate, but
not oxalate- also a product of carbon dioxide reduction. It has
yet to be determined if formate is the sole product of the reduction
of carbon dioxide with a Rhodium catalyst.
Lead Coolant Test Facility. JAMES
WAGONER (University of Idaho, Moscow, ID, 83843) SOLI KHERICHA (Idaho National Laboratory, Idaho
Falls, ID, 83415)
The Lead Fast
Generation IV Reactor holds a lot of promise for the future of
Nuclear Power. Before a Lead Fast Reactor (LFR) can be built,
a lot of research has to be conducted. The best way to conduct
this research would be to construct a Lead Coolant Test Facility
(pictured center). The Lead Coolant Test Facility (LCTF) would
be a small scale, prototypical Facility. Electric power rods
would replace the nuclear core and the thermal energy generated
would be dissipated through CO2 and cooling water. In order to
build this facility, drawings must be made and managers must
be convinced that it must be built. These drawings and visual
aids are what I completed this summer.
Measurement of Fair Weather Air Conductivity. NATISSA
MCCLESTER & DALLAS, JR. MONROE (Florence-Darlington Technical
College, Florence, SC, 29501) JEFFREY GRIFFIN (Pacific Northwest
National Laboratory, Richland, WA, 99352)
For the past
4 years, staff at the US Department of Energy’s Pacific Northwest
National Laboratory have been investigating the generation, and
transport of radiation-induced ions near the ground. Baseline
measurements of fair weather atmospheric conductivity are required
in order to estimate ions lifetimes and predict ions detectability
downwind of a radioactive source. Using a Gerdien condenser,
atmospheric conductivity measurements were made over a two week
period, July 10-21, 2006 in the 300 Area of the Hanford Site.
Experimental data, during that time period, show some uniformity,
with atmospheric conductivity values ranging from 1.4 to1.8 x
10^ -14 S/m. These results are consistent with published values
for arid rural desert regions throughout the world. Weather conditions
were similar over the two weeks that the experiments were performed.
Therefore; to obtain more valid background atmospheric conductivities,
future experiments should look into variable weather conditions
and evaluate their effects on atmospheric conductivities at the
site.
Mechanizing Photoelectron Spectrometer at HERS. XIORANNY LINARES
(University of California, Berkeley, Berkeley, CA, 94720)
ZAHID HUSSAIN (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
Superconductors
have been a main topic of scientific research since their discovery
in the 1950s. In the attempt to understand superconductors, researchers
later discovered cuprates. The discovery of these "high-Tc" superconductors
increased scientists’ possibilities of developing room-temperature
superconductors. This development would increase the efficiency
of electric generation, transmission, distribution, and utilization.
This would result in a reduction of generated power requirement,
and thus, a decrease in greenhouse emissions to the atmosphere.
However, the complexity of high-tc superconductors and their
inability to follow the theories of conventional superconductors
has thus far prevented the creation of room-temperature superconductors.
At the Lawrence Berkeley National Laboratory, the research group
under the leadership of Zahid Hussain tests high-Tc superconductors
to describe their properties and how they work. They study electron
systems using a state-of-the-art High-Energy-Resolution-Spectrometer
(HERS) for angle-resolved photoemission experiments. In these
tests, x-rays are flashed on a sample, and electrons are then
emitted via the photoelectric effect. The emitted electrons are
analyzed by a state-of-the-art angle-resolved electron-energy
analyzer (Scienta SES-200) that rotates about the sample. The
electron analyzer measures the angle and kinetic energy of the
electrons, which, through the conservation of energy and momentum,
determines their velocity, scattering rates, and energy. The
information found is used to create a graph portraying the electron’s
momentum vs. its kinetic energy. This graph shows the Fermi surface
of the material. The Fermi surface is the surface of constant
energy in a space that at absolute zero separates the unfilled
orbitals from the filled orbitals. Its shape determines the electrical
properties of the metal since the current is due to changes in
the occupancy of states near Fermi surface. In this way scientists
can determine the properties and composition of the material.
The research group’s testing process is long and time consuming
since they have to rotate the analyzer manually to obtain their
results. To improve their process, I will make a system that
rotates the analyzer automatically and collects data without
the need of constant supervision. I will research the most efficient
way to rotate the analyzer, make accurate drawings of the system,
make the parts needed for the system, assemble it, test it, and
integrate it for future use.
MEMS Optical Force Probe. KEVIN LIN (University
of California, Berkeley, Berkeley, CA, 94720)
JACK KOTOVSKY (Lawrence Livermore
National Laboratory, Livermore, CA, 94550)
This work seeks
to design small and tunable optical force probes to measure compressive
loads. As the sensor will be placed between two surfaces, a major
goal is to minimize the thickness of the sensor. Optical sensors
based on fiber optic and Micro-electro-mechanical systems (MEMS)
technology allow for small, versatile, and accurate sensors.
These sensors do not use electricity, and offer numerous advantages
over traditional sensors. Fiber Bragg Gratings (FBGs) are treated
fibers that have a periodically varying index of refraction to
give a distinct reflection and transmission spectrum. This spectrum
is dependent on strain, caused either by a transducer attached
to the fiber or thermal expansion. A challenge of this work is
to create a MEMS structure that transduces transverse loads to
fiber strain while compensating for thermal expansion. The limitations
of silicon and the size of the device introduce many challenges.
Finite Element Analysis (FEA) simulates the mechanical and thermal
behavior of the MEMS transducer and its micro-beams to determine
a suitable geometry (i.e. angle, length, and height). Various
metal coatings, solders, and soldering techniques are examined
to determine a repeatable and reliable method for sensor assembly.
Groove cross-sections are optimized for superior fiber to silicon
bonding. Novel schemes assist in the alignment and assembly of
the sensor. An optical force sensor using FBGs has been designed
with a total thickness of 140um (similar in thickness to a fiber
optic cable), insignificant thermal sensitivity, tuneability
to different applied pressures, and mass manufacturability. Its
fabrication is currently underway.
Minimizing Thermal Fluctuations and Vibration Effects on a High Resolution
Beamline. ALFREDO TUESTA (University
of Notre Dame, Notre Dame, IN, 46556) NICHOLAS KELEZ (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
Thermal fluctuations
from the environment and vibrational impacts from surrounding
equipment pose a threat to the performance of high resolution
beamlines. An optimal solution is unknown because methods for
addressing these issues have never been empirically tested. This
research focuses on the support structures, or stands, of MERLIN
(meV resolution beamline) but the results can be applied to any
beamline. The team measured the ground vibrations at several
locations of the Advance Light Source (ALS) where MERLIN will
be installed. Two stands, one empty and one filled with Zanite® Polymer
Composite (Zanite), were also tested to determine the amplification
of vibrations from the ground to the top. The change in the temperature
of the top and middle of the empty stand was also recorded along
with the change in ambient and floor temperatures for two and
a half days. The ground measurements show little change when
nearby equipment is turned off. Additionally, the RMS displacement
is lower than the team’s goal of 0.5-1 micron. The empty stand
shows voltage peaks at 40, 60, and 120 Hz, the later two which
are damped in the stand filled with Zanite. The air temperature
at the ALS changed 1.2°C making the stand temperature fluctuate
approximately 0.8°C yielding a 9.8 microns axial deflection.
This suggests that the stand must be insulated or filled with
a material that will increase its thermal mass in order to decrease
its deformation. Zanite should provide this thermal mass, however,
more time was necessary to confirm this. Due to experimental
error and equipment failure, the results for the ground vibration
measurements are sometimes unclear or erroneous. More time was
required to rectify these issues and to continue measurements
of other methods for solving the thermal fluctuation and vibration
effects at the ALS.
Modeling an antenna using XFDTD. GAURAV
JAIN (Georgia Tech, Atlanta, GA, 30332) PAUL EWING (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
RFID or Radio
Frequency Identification is currently one of the biggest areas
of interest in electronics and sensor technology. From its advent
in the early parts of the 20th century, it has grown rapidly
and has become an integral part of our daily life. This can be
seen from the use of barcodes on items at the mall to the Fast
Pass that is being used in many states at tollbooths. With its
wide range of applications, RFID technology is very valuable
and the present research has consisted of understanding the fundamentals
of RFID and modeling a given antenna in the computer. The software
used for the modeling was XFDTD, which uses the concept of Finite
Difference Time Domain (based on Maxwell’s equations) to generate
the behavior of actual radio waves. The project began by taking
apart the antenna to study underlying circuitry, and it was concluded
that the sample consisted of patch and micro-strip antennas.
Once the design of the antenna was fully understood, the next
step was to develop it within the software. This was the core
part of the project, as the dimensions had to match the original
antenna precisely if there were to be any conclusive results.
This was achieved by using measuring tapes, meter scales and
vernier calipers. Once the completed design in the software resembled
the actual antenna in geometry, its precision was tested by comparing
the results from the network analyzer. The network analyzer gives
the S11 (Input
reflection coefficient) graph of the actual antenna and XFDTD
can generate a similar graph of the s-parameter and by their
resemblance the accuracy can be estimated. The first sets of
models were a bit off the mark due to an inaccurate value assumed
for the dielectric constant. This was corrected by making a rough
parallel plate capacitor and using that to obtain the values
of the dielectric constant. Consequently, the model antenna was
able to produce satisfactory conclusions as the results were
in accordance with the output from the network analyzer. Hence
the understanding and validity of the software was certified.
Although, nothing new was produced from the research, the project
was still successful because it gave an insight into the workings
of RFID technology and how it can be altered to produce results
that are more effective. In a future semester, there will be
a chance to develop upon what was learnt and thereby come up
with new antenna designs that would improve the workings of the
current instruments.
National Synchrotron Light Source-II (NSLS-II) Initial
Conceptual Design Report. ERIC CHANG (Carnegie Mellon University, Pittsburgh, PA, 15213)
ALAN RAPHAEL (Brookhaven National Laboratory, Upton, NY, 11973)
The National
Synchrotron Light Source II (NSLS-II) is an anticipated $700
million medium energy storage ring designed to deliver constant
brightness and flux for hundreds of scientific experiments each
year at the Brookhaven National Laboratory (BNL) in Upton, NY.
Once operational, NSLS-II will have a diameter of 794 feet and
be able to deliver x-rays 10,000 times brighter than the existing
National Synchrotron Light Source (NSLS-I) facility. The Department
of Energy granted the NSLS-II building proposal "Critical
Decision Zero" (CD-0) approving of the facility, allowing
site planning to begin (CD-1). The primary project objective
was to draft an initial plan for utility placement and an underground
emergency tunnel servicing the NSLS-II facility using AutoDesk
Architectural Desktop AutoCAD software and a collection of site
maps of the entire facility as drafting tools. Among the utilities
that were to be supplied are electrical, communication, storm
water, fire protection, sanitary, and steam. By analyzing the
topography of the site as well as the underground placement of
currently operational utilities, the exact depth locations and
routing of the various utilities could be completed. Once all
the utilities were stemmed from existing lines and drawn on the
utility site maps of the facility, an updated map of the facility
and in depth depiction of each line was produced. In addition
to utilities, an underground tunnel was conceptualized for the
use by emergency vehicles. Using the sitemaps, utility investigations,
and geotechnical reviews of groundwater history, distance calculations
indicated the prime location for the tunnel and later modeled
on the computer. The project is a small portion of the much larger
planning stages involved for the NSLS-II construction as summarized
in a Conceptual Design Report (CDR), which also outlines a budget,
scheduling, and environmental/health concerns. With the updated
utility maps and models produced, the CDR will be able to better
plan the NSLS-II facility accounting for the utilities research
and tunnel conceptualization performed. As plans for NSLS-II
are finalized and sent for approval, it is expected construction
will begin in 2008 and operational in 2012.
Opportunities for Direct Current Power Distribution in Commercial Buildings. PEARL DONOHOO (Franklin W Olin College of Engineering, Needham, MA, 29492)
MICHAEL DERU (National Renewable Energy Laboratory, Golden, CO,
89401)
Direct current
(DC) systems in commercial buildings have the potential for energy
savings through increased motor efficiency, elimination of rectifiers,
and use of distributed generation of renewable energy. These
potential savings are documented through past studies on power
supply efficiency, motor efficiency, and new concepts in DC distribution.
Despite alternating current (AC) distribution, components of
heating, ventilation, and air conditioning (HVAC) systems, fluorescent
ballasts, and plug loads all use DC power. To quantify energy
savings, a DC system model of the Pennsylvania Department of
Environmental Protection Cambria Office building was completed.
The three major building systems, HVAC, interior lighting, and
plug-load were modeled, which covered 96% of building energy
use. The buildings systems were modeled twice using data from
a previous study of the building, first assuming one large rectifier
and secondly assuming supplied DC power. The model predicted
an annual average savings of $2,700 with a rectifier and $3,200
without.
Performance Comparison between Graphite and Metallic
Bipolar Plates in Direct Methanol Fuel Cell (DMFC). RAJA CROWLEY
(Farmingdale State University, Farmingdale, NY, 11735)
DR. DEVINDER MAHAJAN (Brookhaven National Laboratory, Upton, NY, 11973)
The use of
Direct Methanol Fuel Cell (DMFC) is an electrochemical process
without combustion as an alternative source of energy. A DMFC
can produce energy constantly, unlike a Lithium battery which
stores energy and after all energy is used up, a battery must
be recharged for a long period of time. Since methanol is available
in a liquid form, it requires minimum storage volume and is easy
to transport. DMFCs have been used in different hand held applications
such as cell phones and laptop computers. There are many parameters
that have an effect on the performance of the DMFC such as the
methanol concentrations, fluid and air flow rate, temperature,
and the humidity level inside the air side of the cell. In this
experiment a performance comparison between graphite and metal
treated plates was studied with different methanol concentrations
with and without humidification. Membrane Electrode Assembly
(MEA) for DMFC with an active area of 2.54cm x 2.54cm, Pt/Ru
catalyst in the anode side and Pt. catalyst in the cathode side,
were used in two single fuel cells, one with graphite plates
and the other with treated metal plates. The liquid methanol
was fed to the cell at a rate of 6 ml/min. Methanol concentrations
of 3%, 5%, 7%, and 10v% diluted in distilled water were used
in both cells, under room temperature, 15psi air pressure, and
an air flow rate of 1.0 SCFH. 3% and 5% methanol concentrations
showed an optimum performance in graphite and metallic plates
respectively. The 3% methanol concentration yielded 29% higher
performance in the metallic bipolar plates and the 5% methanol
showed 45 % higher performance in the metallic plates relative
to graphite. Graphite Plates with 3% and 5% methanol concentrations
with 40% humidity at the air side resulted in 16% and 21% improvement
in performance respectively. While metallic plates with 3% and
5% methanol concentrations, after similar humidification was
applied, showed 2%, and 9% improvement in performance respectively.
Accordingly, it was concluded that the metallic bipolar plates
showed higher performance than the graphite plates, and controlled
humidification in the vicinity of 30% to 50% has positive influence
on the performance of the cell. Humidification had more effect
on the graphite plates than the metallic plates and was attributed
to the surface energy of both materials. Future work will focus
on optimization of the performance of the single cell and to
build a stack of DMFC to power a mobile phone.
Performance of Advanced High Strength Steel Spot Welds. AMEER
TILLMAN (washington state, pullman, WA,
99163) NOVELLA BRIDGES (Pacific Northwest National Laboratory, Richland, WA, 99352)
Resistance
spot welding is one of the primary joining methods for automotive
structural materials. Testing and categorizing resistance spot
welds (RSW) of advanced high strength steel joints was performed
to determine the relationship between failure mode, weld fusion
zone size, and peak load for use in the automotive manufacturing
industry. Static weld strength tests using lap shear samples
were performed on joint populations with controlled weld sizes:
small, nominal, and large. The materials of interest were Dual
Phase steels and Transformation Induced Plasticity (TRIP) steels.
The results of this study will show us whether the current methodology
to determine whether a RSW joint is satisfactory is valid for
advanced high strength steel RSW joints.
Performance of Generation 3 High-power Lithium-ion Trial Cells. AVERI ESCALONA (University of Illinois at Chicago,
Chicago, IL, 60606) IRA BLOOM (Argonne National Laboratory, Argonne,
IL, 60439)
Li-ion batteries
have proven to be a successful energy source for many consumer
electronic devices. Research is now being done to develop this
technology for other applications, particularly as an energy
source for hybrid electric vehicles. The Freedom Cooperative
Automotive Research (FreedomCAR, formerly known as the Partnership
for the Next Generation of Vehicles) has developed certain goals
and standards for high-power, Li-ion battery cells for vehicular
application. The U.S. Department of Energy’s Advanced Technology
Development Program addresses issues related to meeting these
goals and standards. The program consists of a series of five
projects, including the development of a baseline generation
of cells (Generation 1) and an evaluation of it, followed by
improved iterations (Generations 2 and 3) and finally low-cost
packaging for the cells. The Electrochemical Analysis and Diagnostics
Laboratory at Argonne National Laboratory evaluated and compared
the performance of eight different trial Li-ion cell chemistries
to the cell performance of a previous generation (Generation
2, or Gen2) of cells in order to determine an optimal cell composition
for the next generation (Generation 3, or Gen3) of cells for
a larger study. Good cell performance was evaluated in this particular
study in terms of low capacity fade over time and low impedance
rise over time. Characterization was done at the beginning of
the study to establish a baseline for trial cell performance
over time. Calendar-life aging was used as a method of cell degradation,
with reference performance tests performed at four week intervals
in order to gauge change in cell performance over time. Testing
is still in progress, but initial results show that the capacity
retention of one of the Gen3 trial chemistries, the 700-series,
is better than that of Gen2, and two of the Gen3 trial chemistries,
the 600- and 700-series, have a rate of impedance rise similar
to that of Gen2. All Gen3 trial chemistries have both lower capacities
and higher impedance than the Gen2 chemistry, but it is possible
to attribute this to factors such as poor cell composition or
physical damage. Based on this initial data, the 700-series cells
should be considered for further study.
Performance Testing of Radio Frequency Identification Tags and Evaluation of
Russian Radio Frequency-Based Tamper Indication Devices for
Nuclear Safeguards. BEN PETERS (Maryville College, Maryville, TN, 37830) CHRIS A. PICKETT (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Two promising
technologies that are being evaluated to help in nuclear material
control and accountability are Radio Frequency Identification
(RFID) tags and active radiofrequency (RF)--based Tamper Indication
Devices (TIDs). There are both active and passive RFID tag systems.
Passive RFID systems utilize a reader that induces the passive
tag to transmit an RF signal back to the reader in the form of
a unique digital identification number. Active tags, on the other
hand, are battery powered and continuously transmit an RF signal.
Two kinds of active RF-based TIDs supplied by a Russian laboratory
were also tested at ORNL. The two TIDs are RF tags that utilize
fiber-optic technology to create a loop-type seal, along with
bolt seals, which use either a piezoelectric generator or galvanic
power cell to provide power to the seals. The active RF TID tags
were installed on actual radiological storage containers and
evaluated in operation over several weeks. Several RFID tags
and readers were characterized to determine read ranges and the
effects associated with orientation and placement of the tags
on metal storage containers. Ten RFID tags of each type (active
and passive) were used in order to determine read range variance.
Multiple trials were conducted using tags positioned at four
different angles in relationship to the antenna. After multiple
trials, the results illustrated that there are both benefits
and limitations to using both these technologies for safeguards-related
applications. The performance of the passive RFID tag system
was primarily affected by the antenna size, as well as with the
tag size and type. If these factors are considered during system
design, an effective RFID system can be developed to maximize
the read range and, therefore, the number of reads. The problems
seen with the Russian TIDs were mainly associated with the design
of the tag or bolt themselves. More testing and possibly some
design changes will be needed before any final recommendations
can be made.
Polycrystalline Ceramic Scintillators. ANDREA
NORTH (University of Tennessee, Knoxville, TN, 37934) DANNY POWELL (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Scintillators
are a vital component of radiation detection in numerous applications,
including medical diagnostics and imaging, nuclear nonproliferation,
and scientific research. Due to the demand for these detectors
and the limitations of single-crystal scintillators, research
of transparent polycrystalline ceramic scintillators has become
increasingly attractive. This research has potential advantages
for scintillation materials, such as the ease of fabrication
and the ability for duplication. Recent studies of ZnO: Ga and
Lu2O3: Eu have shown promise as potential transparent polycrystalline
scintillators. However, additional studies are required to improve
the transparency, size, and quality of the densified bodies.
After ensuring the purity of the materials, the powders are combined
both manually and chemically to create a homogenous mixture.
The powders are densified into a transparent ceramic through
hot or cold pressing, vacuum sintering, and pulsed electric current
sintering. The first method to be applied on these samples is
hot press. The pellets are then tested for the important scintillation
properties of decay time, light output, timing resolution, and
energy resolution. Because this process is extensive and testing
requires a significant amount of time, the project has not yet
been completed. However, visual analysis of the ceramic after
the hot pressing technique shows promise for these samples. The
results from the ZnO: Ga and Lu2O3:
Eu will enhance the knowledge of their capabilities and could
also increase the abilities for radiation detection. Further
work will involve different sintering techniques with these samples
and also the testing of other samples. This is a very small portion
of the research for improved scintillation materials that will
mitigate the limitations of single-crystal scintillators.
Power Grid Dynamics: Enhancing Power System Operation through Prony Analysis. CODY RAY (Oregon State University, Corvallis, OR, 97331)
ZHENYU HUANG (Pacific Northwest National Laboratory, Richland, WA, 99352)
Prony Analysis
promises to be an efficient way of recognizing sensitive lines
during faults in power systems such as the U.S. Power grid. We
use Positive Sequence Load Flow (PSLF) to simulate a simple two-area-four-generator
system, and the dynamics the system experiences during a line
fault. We then use the Dynamic System Identification (DSI) Toolbox
to perform Prony analysis and use modal information to identify
key transmission lines for power flow adjustment for improving
system damping. We report on the success of the application of
Prony analysis methods to the data obtained from PSLF, and the
identification of the key transmission line for adjustment. Future
work will focus on larger systems, and improving the current
algorithms to deal with networks such as large portions of the
Western Electricity Coordinating Council (WECC) power grid.
Power Performance Analysis of Wind Turbine Generation Systems. LAUREN
COOPER (Colorado School of Mines, Golden, CO, 80401)
ARLINDA HUSKEY (National Renewable Energy Laboratory, Golden,
CO, 89401)
Modern wind
technology is among the most effective and profitable ways to
simultaneously address global warming and meet America’s growing
energy needs. Nevertheless, further advancements, including the
optimization of offshore wind turbines, will be necessary for
continued success in the United States. This paper describes
a MATLAB-based rotor design optimization program called Rotor
Optimization for Offshore Turbines (ROOT) that includes both
land-based and offshore cost models. The program uses MATLAB’s
Genetic Algorithm Tool to find the rotor radius, number of blades,
chord distribution, and twist distribution that result in a minimum
cost of energy (COE) for a given wind regime. To predict aerodynamic
performance, ROOT uses a program developed at the National Wind
Technology Center called WT_Perf, which relies on blade element
momentum theory. ROOT includes a basic structural analysis as
well as losses due to soiling, wind farm array effects, availability,
and power conversion. Although ROOT requires further development,
such as improvements in the structural and cost models, the version
discussed in this paper proved to be an effective rotor design
tool. ROOT consistently generates blade shapes that closely resemble
existing designs, even when the program begins with a random
set of geometrically unusual designs. For a wind regime near
the Nantucket Sound, ROOT generated a rotor design that would
improve COE by 4.6% over the baseline design.
Pressure Loss in Cooling Channels Enhanced with Wire-Coil Inserts. WILLIAM O'BRIEN (Community College of Rhode Island,
Warwick, RI, 2886) JEFF T. COLLINS (Argonne National Laboratory,
Argonne, IL, 60439)
Front end high-heat-load
components of the insertion devices and bending magnets at the
Advanced Photon Source (APS) are cooled with deionized (DI) water
flowing through cooling channels that have oxygen free copper
(OFC) wire-coils inserted into them to enhance convection heat
transfer. The pressure loss across these cooling channels must
be studied to optimize the design parameterized friction coefficients
of the enhanced cooling channels and bulk fluid velocity of the
DI water. One OFC test tube is used, with a 0.375 inch hydraulic
diameter, made to accommodate the 13.5 inch long OFC wire-coil
inserts. A matrix of OFC wire-coil inserts is fabricated in house
with wire diameters ranging from 0.035-0.125 inches and different
coil pitches ranging from 0.091-1.00 inches. Water is deionized,
sterilized, filtered, and sent through a system of circuits designed
to test flow rates across laminar, transitional, and turbulent
flow regimes. Pressure loss, flow rate, and temperature readings
are collected and reduced to dimensionless quantities used to
develop four equations correlating channel size, wire diameter,
wire-coil pitch, mechanical fluid properties, and bulk fluid
velocity of the DI water throughout laminar and turbulent flow.
The correlation established will provide thermal engineers in
the synchrotron light source community functions that predict
coil pitch and wire size based upon design geometry and pressure
loss needs.
Process Engineering for Hydrogen Production Plants Using High Temperature Steam
Electrolysis. ALEJANDRO SAUCEDO (Illinois Institute of Technology,
Chicago, IL, 60616) MARIBEL VALDEZ (Illinois Institute of Technology,
Chicago, IL, 60616) DR. RICHARD DOCTOR (Argonne National Laboratory,
Argonne, IL, 60439)
Hydrogen fuel
production is a stepping-stone towards eliminating dependency
on fossil fuels. A potential method for mass production uses
High Temperature Steam Electrolysis (HTSE). HTSE is a thermo-chemical
process that splits a water molecule into hydrogen and oxygen.
It requires a solid oxide electrolysis cell (SOEC) that operates
at 1100 K with an yttrium-stabilized zirconium electrolyte. Potentially,
the Gen IV nuclear reactor will be used as a power source to
meet temperature requirements without greenhouse emissions. Currently,
two process simulations for large-scale hydrogen production using
HTSE have been introduced by Argonne National Laboratory (ANL)
using ASPEN computer software and Idaho National Laboratory (INL)
using HYSYS computer software. The economic feasibility of both
processes must be determined thus a cost analysis of fluid transport
and heat transfer equipment is conducted, and the energy balance
is calculated. From these energy calculations, it is discovered
that the optimum energy balance occurs in ANL’s feed case of
50% water and 50% hydrogen. From the equipment cost analysis,
it is estimated that for ANL the total process equipment cost
is $73 million, whereas for INL it is $40 million. For both,
ANL and INL systems, the total initial cost of the electrolysis
unit and the nuclear reactor is about half a billion dollars.
Although a HTSE hydrogen production plant will involve huge upfront
investments in resources, this comparative economic analysis
provides a basis for HTSE system selection.
Process Engineering for Hydrogen Production Plants Using High Temperature Steam
Electrolysis. BHARAT THAKKAR (Illinois Institute of Technology,
Chicago, IL, 60616) DR. RICHARD DOCTOR (Argonne National Laboratory,
Argonne, IL, 60439)
Two process
simulations for large-scale hydrogen production using High Temperature
Steam Electrolysis(HTSE) have been introduced by Argonne National
Laboratory (ANL) using ASPEN computer software and Idaho National
Laboratory (INL) using HYSYS computer software. The economic
feasibility of both processes must be determined thus a cost
analysis of fluid transport and heat transfer equipment is conducted,
and the energy balance is calculated. From these energy calculations,
it is discovered that the optimum energy balance occurs in ANL’s
feed case of 50% water and 50% hydrogen. From the equipment cost
analysis, it is estimated that for ANL the total process equipment
cost is $73 million, whereas for INL it is $40 million. For both,
ANL and INL systems, the total initial cost of the electrolysis
unit and the nuclear reactor is about half a billion dollars.
Although a HTSE hydrogen production plant will involve huge upfront
investments in resources, this comparative economic analysis
provides a basis for HTSE system selection.
Production of Syngas for Fischer-Tropsch Synthesis. LANE KNIGHTON
(Brigham Young University, Provo, UT, 84606) LANCE LAUERHASS (Idaho National Laboratory, Idaho
Falls, ID, 83415)
Objective:
Analyze various operations involved in production of syngas and
Fischer-Tropsh (FT) liquids to optimize generation of desirable
products and predict the amount and type of products generated
per feedstock type and amount. Fischer-Tropsch synthesis is used
to make synthetic fuels such as diesel fuel and gasoline. Interested
companies have asked INL to perform such process simulations
in order to have an idea of the products they can generate as
well as the waste that must be cleaned and disposed of. Background:
Syngas is mainly a mixture of H2 and CO along with some impurities.
Syngas is generated by gasifying or pyrolyzing organic material
at high temperature. Typical feedstock can include: 1) Used tires
(tire-derived fuel or TDF) 2) Biomass 3) Coal (CTL-Coal to liquids)
4) Natural gas (GTL-Gas to Liquids) 5) Municipal Solid Waste
(MSW) 6) Plastics Waste 7) Carpet fluff 8) Any other carbon containing
material or waste The feedstock used in these simulations were
TDF, herbaceous, and carpet fluff. Willow, corn stover, wood
chips, and straw compositions were averaged and used as the herbaceous
feedstock. Some uses for syn gas are shown in Figure 1. Some
uses that are receiving attention now are Fischer-Tropsch synthesis
and power generation. Some companies desire to have hybrid plants
that divert a portion of the syngas to produce electrical power
by means of a gas turbine & generator setup, while diverting
the rest of the syngas to produce FT liquids. The optimum combination
between power generation and FT liquids production from an economical
standpoint is being investigated. Some industries such as steel,
paper making, etc… want to have small scale gasifiers on site
to provide process heat and power generation for the plant.
PROTEIN EFFECTS ON THE MICROSTRUCTURE OF DOPED SILICA AEROGELS. BRANDI DOYLE (Texas Tech University, Lubbock, TX,
79401) JAN ILAVSKY (Argonne National Laboratory, Argonne, IL,
60439)
Silica aerogels
(AGs) are inorganic polymers with low density which are used
in a wide variety of sensor applications. By doping the silica
gel with cadmium sulfide (CdS) and myoglobin, a biocomposite
AG used in biosensors is formed. Through better understanding
of the microstructure of these porous solids, their properties
can be improved and tailored towards specific applications. Silica
AGs doped with a myoglobin protein in five different ratios were
synthesized and then examined through ultra-small angle X-ray
scattering (USAXS). Through the USAXS we expect to see an increase
in the size of the protein superstructure with increasing amounts
of myoglobin. The log-log plots of the Silica AGs doped with
protein consistently show three structural levels, with the first
pertaining to the protein superstructure. Through the comparison
of the radius of gyration (Rg) which corresponds to the protein
size with the percent of myoglobin in the protein mixture, the
particle size of the superstructure does not show an increase,
or any trend for that matter. Through future investigation we
can determine if the percent myoglobin truly has no effect on
size of protein superstructure or if there were other factors
during sample preparation that affected their growth.
Remote Handling Tooling for the Spallation Neutron Source. DAVID
MACNAIR (Georgia Tech University, Atlanta, GA, 30332) CRAIG BRADLEY (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
The Spallation
Neutron Source (SNS) will smash accelerated protons into liquid
mercury which will create the most powerful neutron scattering
facility in the world. When protons hit the mercury, the mercury
becomes radioactively activated and the stainless steel housing
for the mercury (the target) erodes. Every three months this
target will be replaced, requiring the target cart to back into
the target cell where manipulators, servo manipulators, and a
crane change the target and perform needed maintenance. These
operations require special remote handling tools to be designed,
fabricated, and tested before the SNS comes online and the target
cell becomes inaccessible. One of many tools worked on this semester
is the lift compensator, which serves as a backup to the target
cart hydraulic drive system. The compensator connects the overhead
crane and the target cart backup jacks and will stretch like
a spring giving the operator a gage on force applied to the jacks.
Since the jacks fail at about 10,000 pounds of force, a break
link was added which fails at 5,000 pounds and protects the backup
jacks from damage. The spring in the compensator consists of
seventy six Belleville washers stacked in series giving the operator
6.5 inches of movement between unloaded and 5,000 pounds. All
components were designed using the solid modeler Pro/Engineer
and then analyzed using hand calculations and finite element
analysis with Pro/Engineer Mechanica. Results of the stress calculations
were reviewed by the remote handling group and the SNS division,
and finally the drawings were sent for fabrication. Fabrication
has not finished, and no final results for the effectiveness
of the design are available. Due to the magnitude of the project
and the inaccessibility of the target cell by humans during SNS
operation, each component inside the target cell must be carefully
designed, analyzed, and tested before the SNS starts up. Additionally,
components must be easily accessible, maintainable, and maneuverable
by remote handling equipment so that the SNS can enjoy scientific
discovery even beyond the length of its original design.
RESOURCE CONSTRAINT’S ROLE IN THE TRANSITION TO A CLOSED SELF SUFFICIENT GLOBAL
NUCLEAR FUEL OPTION. TIMOTHY ROGERS (Texas A&M
University, College Station, TX, 77843) DAVID C WADE (Argonne
National Laboratory, Argonne, IL, 60439)
With uranium
ore deposits estimated at about fifteen million tonnes, it is
necessary to determine an optimal ore withdrawal strategy to
ensure nuclear energy sustainability. Producing this strategy
requires optimization of virgin ore usage so that enough fuel
is available to introduce fast breeder reactors as well as secure
transportable autonomous reactors. To find an optimal ore withdrawal,
a classical mechanics mathematical model is used. State equations
of the system form the state matrix, with the control matrix
being the ore withdrawal of uranium and the transuranic fuel
for each reactor type as a function of time which is simulated
over the time interval chosen to find the final conditions. An
adjoint solution is then found to construct the Hamiltonian variation
with respect to the control matrix. This gradient is then subtracted
off to produce a more optimal ore withdrawal control. This process
is iterated to minimize the performance index, which is based
on the power mismatch between target and actual powers, and then
to maximize ore withdrawal to meet power demand. This provides
the user with the best possible ore withdrawal strategy to ensure
nuclear power growth. Results of this code are dependent on the
user input and thus can vary over wide ranges of ore withdrawals.
Output from this code shows the implications of introducing reactors
that can create fuel. It also shows how early implementation
of these types of reactors can help to alleviate the world’s
future power needs. As for future use of these results, it will
be possible to use the optimal ore withdrawal as part of a high
fidelity model that accounts for more factors relevant to nuclear
power growth.
Rotor Design Optimization for Offshore Wind Turbines. PAUL KREINER
(Stanford University, Stanford, CA, 94305) PATRICK MORIARTY (National Renewable Energy Laboratory, Golden,
CO, 89401)
Modern wind
technology is among the most effective and profitable ways to
simultaneously address global warming and meet America’s growing
energy needs. Nevertheless, further advancements, including the
optimization of offshore wind turbines, will be necessary for
continued success in the United States. This paper describes
a MATLAB-based rotor design optimization program called Rotor
Optimization for Offshore Turbines (ROOT) that includes both
land-based and offshore cost models. The program uses MATLAB’s
Genetic Algorithm Tool to find the rotor radius, number of blades,
chord distribution, and twist distribution that result in a minimum
cost of energy (COE) for a given wind regime. To predict aerodynamic
performance, ROOT uses a program developed at the National Wind
Technology Center called WT_Perf, which relies on blade element
momentum theory. ROOT includes a basic structural analysis as
well as losses due to soiling, wind farm array effects, availability,
and power conversion. Although ROOT requires further development,
such as improvements in the structural and cost models, the version
discussed in this paper proved to be an effective rotor design
tool. ROOT consistently generates blade shapes that closely resemble
existing designs, even when the program begins with a random
set of geometrically unusual designs. For a wind regime near
the Nantucket Sound, ROOT generated a rotor design that would
improve COE by 4.6% over the baseline design.
Safeguarding America By
The Monitoring Of Semi-Trucks Using Programmable Logic Controllers. WILLIAM
SMITH (Middle Tennessee State University, Murfreesboro, TN, 37132)
DAVID HILL (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
With the constant
growing threat of terrorist attacks on the United States, the
SensorNet program, at the Oak Ridge National Laboratories, is
discovering ways on making their attempts exceedingly difficult.
SensorNet in conjunction with the Southeast Trusted Corridor
program is doing this by the monitoring, tracking, and the collecting
of information on semi-trucks through the U.S. weigh stations.
By gathering information such as license plate numbers, US DOT
numbers, radiological data, weight, and numerous photographs
of specified locations on the semi-truck, records can be made
and stored to a database, which can be used to track the trucks
all over America and whether or not if the trucks have acquired
any sort of substance that could be considered a threat. Gathering
some of this information is done by using distance-to-object
(DtO) lasers and Programmable Logic Controllers (PLC). PLC’s
are microcontrollers that can be programmed, with a ladder logic
code, to use analog or digital input devices. These input devices
can control external device, counters, timers, mathematical logic,
messages, and other equipment in the memory of the PLC. The old
system of monitoring the trucks used an OSI Laser scanner. The
problem with this concept was that the laser scanner was only
at the beginning of the weigh station, and there was no way to
pinpoint where the truck was after the truck had passed the laser
scanner to get accurate data or pictures. With the new system,
the DtO lasers are placed in specific locations along the weigh
station and when the beams are broken, the PLC will send a message
to the computer that will direct the cameras when to accurately
take photographs, and to collect data from the radiation detectors.
The PLC will, in addition, calculate the speed of the trucks
in three different locations on the scale, along with the average
speed which will configure into the accuracy in the radiation
detectors. Meanwhile, the PLC will also be counting the number
of axels the trucks have, and the number of trucks that pass
through the scales each day, week, month, and year. With the
collection of this information, the men and women of the police
departments around the U.S., can identify which trucks are posing
as a threat, and to be able to take the necessary actions to
keep the citizens safe from harm.
Self-Powered Oil-Fired Heating System based on Thermophotovoltaic
Power Generation. EVELYN
MEJIA & MARTIN NOLAN (The City College
of New York, New
York, NY, 10031)
THOMAS BUTCHER (Brookhaven National Laboratory, Upton, NY, 11973)
Self-powered
appliances, such as a home heating system, have the potential
to operate independently from the electric power grid. Thermophotovoltaic
(TPV) power generation is well suited for self-powering. This
involves generation of electric power by converting radiant heat
emitted by a high temperature emitter into electricity using
photocells. Since the amount of power generated depends on how
much energy is emitted, the radiant emitter becomes an important
component of the TPV converter. In this project, a self-powered
oil-fired heating system based on thermophotovoltaic power generation
was designed and analyzed. For this project, computational and
experimental analyses were used to maximize the emitter temperature,
measure the emitter temperature distribution, and vary the geometry
of the experimental setup in order to reach the desired temperature.
The computational fluid dynamics (CFD) model simulated the heat
transfer in the combustion chamber. Using the CFD model, possible
changes to the shape of the cylinder, placement of the TPV cells,
and insulation thickness were explored so as to maximize the
emitter temperature and exceed the target of 1300°C. From the
CFD, the experimental analysis was designed; this work was part
of an iterative process of adjusting the model and the experiments
based on their results. The other analysis performed was experimental
analysis; two geometrical cases were considered. In the first
design case, the experiment was performed using a low Nitrogen
Oxides (NOx) (Blue Flame) burner with an open-end cylindrical
Silicon Carbide (SiC) attached as a flame tube. The SiC emitter
was selected because it can withstand temperatures above 1300°C,
which is ideal for energy conversion. The emitter was wrapped
with a refractory blanket and the TPV was placed on the outer
surface of the blanket. In second design case, the flame tube
was simply used to guide the flame toward the emitter, refractory
blanket, and TPV cells that were placed at the open-end of the
combustion chamber like a target wall. The results for the first
case showed the maximum emitter temperature is 1283°C and the
second case, the temperature reached 1465°C. Therefore, the second
case was the ideal approach because it had been successfully
tested to amplify the efficiency of the TPV with the higher temperature.
Single and double Gas Electron Multiplier X-ray Gas
Detector. MARCUS MASON & ELHAG SHABAN (Southern University Baton
Rouge, Baton Rouge, LA, 70813) D. P. SIDDONS (Brookhaven National Laboratory, Upton, NY, 11973)
The purpose
of this research is to present results obtained from testing
of a single and a double GEM X-ray gaseous detector. The detectors
have been designed, assembled, and tested at the National Synchrotron
Light Source (NSLS) at Brookhaven National Laboratory (BNL).The
single and the double GEM detectors are intended to provide a
noise and discharge free amplification to be used for Extended
X-ray Absorption Fine Structure (EXAFS) procedure. A voltage
of 450 volts across the single GEM provided a maximum gain of
900. A voltage of 350 volts across the double GEMs provided a
gain of 9000 without stressing the GEM and creating the possibility
of discharges.
Structure of Phosphatidylcholine Cholesterol Bilayers Using Grazing Instance
Small Angle X-ray Scattering. CHRISTOPHER
LEHMANN (Texas Tech University, Lubbock, TX, 79409) JAN ILAVSKY
(Argonne National Laboratory, Argonne, IL, 60439)
Lipid bilayer
membranes isolate and protect cells in the body. The structure
of cholesterol/lipid bilayer membranes are studied to understand
the manner in which molecules attach and interact at the cell
membrane. This research is to determine whether the membrane
lipids form ordered structure. The presence of regular lipid
structures would affect the manner of drug interaction with the
cell membrane and improve the understanding of the progression
of many diseases associated with cholesterol. In addition, membrane
organization would suggest possible behavior and design of model
cell membranes in mircoarray and microfluidic biochips. In this
work, cholesterol/palmitoyloleyl phosphatidylcholine (Chol/POPC)
bilayers on a glass substrate were studied under grazing instance
small angle x-ray scattering (GISAXS). GISAXS was used to measure
the diffraction patterns and specular reflectivity. GISAXS is
a useful method for lipid membrane research because it probes
the area near the interface and data acquisition is fast, minimizing
sample exposure to high photon fluxes. Research found the concentration
of cholesterol in the bilayer mixture affects the structure of
the membrane. Analysis of the collected data shows diffraction
in more then one sample. For the samples that showed specular
reflectivity the characteristic d-spacing observed is around
40 angstroms. Specular reflectivity suggests that the sample
had regions of uniform structure. Future work should examine
cholesterol concentrations in the range of 20 to 50-mol%. Membranes
with higher mole percent may allow for better imaging because
of the larger differences in electron density, also they closely
mimic lipid/cholesterol compositions found in mammalian cells.
GISAXS will be used in observing the diffraction because it proved
an effective way to measure lipid bilayers at high fluxes. In
addition, reflectivity data should be taken on the samples. The
number of layers present from the reflectivity data would confirm
whether a single uniform lipid bilayer is present.
Sulfuric Acid Materials Test Loop. DANIEL
LAMONE (The Ohio State University, Columbus, OH, 43210)
STEVEN SHERMAN (Idaho National Laboratory, Idaho
Falls, ID, 83415)
Several hydrogen
production processes are currently under investigation by the
US Department of Energy (DOE) and several foreign governments,
most notably France and Japan, for use in a co-located nuclear
plant/hydrogen production facility. One of these processes is
the Sulfur-Iodine Thermochemical Process. This process utilizes
a series of chemical reactions that are driven by the thermal
energy from a Very High Temperature Gas-Cooled Reactor (VHTR)
to thermochemically split water into hydrogen and oxygen. The
high-temperature chemical step in this process thermally decomposes
sulfuric acid (H2SO4) at 850° C, imposing extreme demands on
the process materials. To date, little research has been conducted
in the US to study the long-term effects of these conditions
on structural materials and components, and there are no existing
facilities beyond the bench-top for performing such tests. Therefore,
there is a need for a closed experimental loop containing sulfuric
acid that is capable of exposing samples and integrated components
(e.g. heat exchangers, valve designs, etc.) to sulfuric acid
decomposition products at high temperatures (750-850 °C) for
long periods of time. The loop must be capable of long-term,
continuous operation (hundreds to thousands of hours) under simulated
operational conditions that are to be found in the actual production
facility, accommodate different component prototype designs and
their respective testing requirements, and operate safely during
all periods of operation. This loop will be built and operated
at a US Department of Energy (DOE) facility or partner facility
under the direction of the DOE Nuclear Hydrogen Initiative (NHI).
This project provides a conceptual design for such a materials
and component test loop and will serve as a starting point for
more the more detailed design and safety analysis work that will
be needed once the loop is scheduled for construction and operation.
Synthesis and Electrochemistry of Composite-structured Lithium Nickel Manganese
Oxides for Lithium Batteries. JENNIFER
GATES (Fayetteville State University, Fayetteville, NC, 28301)
CHRISTOPHER JOHNSON (Argonne National Laboratory, Argonne,
IL, 60439)
Low weight
and volume, high energy and power density, stability over many
cycles, a large range of operating temperature, low cost, and
safety are desired properties in all secondary batteries, but
particularly those that are used in cell phones, laptops, and
hybrid vehicles. Lithium’s low molecular weight and very negative
reduction potential place lithium-ion batteries in a good position
towards meeting these goals, but much work must be done towards
improving the batteries. In batteries that are currently used
in cell phones, a lithium-graphite intercalation solid is the
anode and the cathode is LiMn2O4 or LiCoO2. We investigated (1-x)LiNi0.5Mn0.5O2•xLiNi0.5Mn1.5O4
composites, where x is varied from 0 to 1 in increments of 0.1,
as a cathode material, in order to try to improve the capabilities
of the cathode. The compositions we studied are composites of
a layered and a spinel oxide phase. A composite structure may
be expected to have a greater stability to lithium insertion/extraction
due to synergism between the two phases. Many new lithium metal
oxides were synthesized and optimized for phase purity and structure.
Electrochemical characteristics are being studied such as current
rate, cycle life, stability, and safety in "coin cells".
The coin cells were made using lithium metal as the anode; ethylene
carbonate (EC) and ethyl methyl carbonate (EMC) in a ratio of
3:7 respectively as the solvent, and LiPF6 as the electrolyte.
The current density was 0.10 mA/cm2, which gives approximately
20 h discharge or charge time.
Testing and Development of Neutron Bubble Dosimeters for Upgrading Radiation
Monitors. PHILLIP ZELLNER (Virginia Polytechnic Institute and
State University, Blacksburg, VA, 24060) ERIK ABKEMEIER (Thomas
Jefferson National Accelerator Facility, Newport News, VA,
23606)
Jefferson Lab
is upgrading its particle accelerator from 6 GeV to 12 GeV to
give physicists greater insight in the experiments they run.
An unfortunate side effect of the upgrade, is that the experiments
performed by Jefferson Lab will generate neutron radiation with
much higher energy (up to 20 MeV). The ion chambers that the
Lab uses to monitor the radiation dose given to the public, will
not be able to detect the higher energy neutrons. In order to
solve this problem, neutron bubble dosimeters are being developed
to detect the higher energy neutrons. These dosimeters are the
first instruments to put superheated bubbles. The ability of
the neutron bubble dosimeters to detect 20 MeV neutrons has already
been proven. However, this project tested the feasibility of
using the neutron bubble dosimeters. The detectors were tested
on Jefferson Lab’s radiation range and calibrated. Then the neutron
bubble dosimeters were tested side-by-side with the ion chamber
dosimeters in the existing radiation monitoring stations. It
was shown that the neutron bubble dosimeters could detect the
higher energy neutrons. The test results from the comparison
of the two types of dosimeters showed that the neutron bubble
dosimeters were at least as reliable as the ion chambers in detecting
the neutrons that are currently produced by the accelerator.
This success ensures that a reliable radiation detection system
will be in place well before the 12 GeV upgrade is complete,
thereby ensuring the safety of Jefferson Lab’s employees and
the public.
Testing of Beam Position Monitor Calibration Software. ELI CARREIRO (Rensselaer Polytechnic Institute, Troy, NY, 12180) THOMAS RUSSO (Brookhaven National Laboratory, Upton, NY, 11973)
New software
has been developed for the Relativistic Heavy Ion Collider
(RHIC) Beam Position Monitor (BPM) hardware. This software
is designed, via calibration, to remove drift within the BPM
motherboard, and to make only one initial time–consuming external
calibration necessary. The data points from the initial external
calibration are saved and utilized in remotely performed internal
calibrations. Testing of the software has made use of the following
instruments and experimental processes: function generators
to simulate the RHIC beam signal to the BPM boards; actual
RHIC beam signal; oscilloscopes to monitor electronic activity
in board circuitry; resistors soldered onto certain points
of the boards in order to introduce artificial drift; and finally,
LabVIEW and NX Client software. NX Client software was used
to read and to plot calibration data obtained from BPM boards,
and LabVIEW virtual instruments were used to vary internal
pulser attenuation values of the BPM boards throughout testing.
After several tests and modifications to the software, the
new version of code proved to be robust in maintaining calibration
over a more than acceptable range of internal pulser attenuation
values. Furthermore, experimentation revealed the software
to be capable of calibrating out simulated drift to well within
accepted error ranges. Testing of BPM boards installed in the
RHIC showed the software to be operational with real beam signal.
The new software is a significant improvement over past systems
and, pending further testing and the implementation of a curve
smoothing algorithm for calibrations utilizing the RHIC beam
data, the software will be employed in all of the RHIC BPM
hardware.
The Solar Hydrogen Home. RODRIGO
PENA (Nassau Community College, Garden City, NY, 11530) DEVINDER
MAHAJAN (Brookhaven National Laboratory, Upton, NY, 11973)
As oil prices
continue to escalate to levels that threaten our economy, alternative
energy is starting to play an important role in our society.
Hydrogen fuel cells and solar panels are alternatives that
promise a non pollutant way of producing energy. A solar cell
is a p-n junction, made out of silicon (semiconductor). A p-n
junction is the product of two layers of the same semiconductor
material that are doped with different materials to leave one
free electron in a layer, and a deficit of one electron in
the other layer. A photon will move this free electron from
one layer to the other, inducing an electrical field at the
interface of these two layers, and a current will flow when
the circuit is closed. A solar energy arrangement (photovoltaic
system) will be used to meet the load of an average household
that requires approximately 10,000 kWhr of energy per year.
The objective of the current work is to put together a cost
effective model house scaled down 1:300 of the energy required
for an average residential home to conduct system and energy
analysis. The Photovoltaic (PV) size facing south required
to meet the load of an average household is 9 kW with efficiency
of 75 % that counts for inverter and wiring losses of the system.
In this project, two solar panels measured at 15 watts each
will simulate the 9 kW PV system. These two solar panels will
be used to feed the total consumption of the model house. In
New York, the average sun hours per day are 4.3 hours, during
which the PV system will produce the total energy needed to
run the house for the whole day. The excess portion of solar
energy that is not used during the 4.3 hours will be used to
electrolyze water and generate hydrogen and oxygen. The hydrogen
is stored in tanks to be used after the sun set to produce
energy on demand by hydrogen fuel cells. The current experimental
work showed that for 9 kW - PV system, the hydrogen production
is one fourth the total amount needed to cover the energy demand
for the remaining hours of the day after sun set. This is attributed
to the efficiencies of the fuel cell and Electrolyzer at the
current state of technology.
The Utilization of Thermoelectrics to Capture Excess
Waste Heat Produced by an Oil Burner in the Pursuit of
Developing a Self-Powered Boiler. JULIAN TAWFIK (Stony Brook University, Stony Brook, NY, 11794) DR. THOMAS BUTCHER (Brookhaven National Laboratory, Upton, NY, 11973)
Thermoelectric
devices produce electric power when exposed to a T (temperature
difference), between the hot and cold junctions. The objective
of this project is to conduct theoretical/conceptual feasibility
and economic studies on the utilization of thermoelectrics
and their ability to produce electricity from temperature gradients
generated by an oil boiler to power its electrical components
and make it electrically self-sufficient, with no need for
a connection to an external power source. The most efficient
installation location of the devices on the boiler and its
components with the appropriate T was determined (on the boiler
wall/exhaust pipe) to produce the 100 watts of electricity
needed to power the auxiliary boiler units. The current analysis
includes the following factors: maximum temperature the thermoelectric
devices could withstand, how many thermoelectrics could be
accommodated on the boiler unit or its components, and cost
effectiveness with return on investment (ROI). A heat sink,
to prevent the overheating of the devices by maintaining the
cold side at ambient temperature was designed. Two bismuth-telluride
thermoelectric units were tested and an IV curve was obtained
(current/voltage) to determine if they would perform under
operating conditions of 155°C T between the boiler wall/exhaust
pipe (175°C) and ambient air (20°C). 10 units of the #219 model,
5.7-watt generators would need to be purchased at a cost of
$419.50. After 20,000hrs the ROI of the units would be $420.00
(a 50¢ gain), which is economically unfeasible. Total burner
surface area required was 291.6 cm2. Results show that making
an oil-burning boiler self-sufficient is possible, but uneconomic
until more efficient and inexpensive materials are available.
Some materials currently being researched are cobalt based
and thin film superlattice thermoelectrics. In conclusion,
the research here has contributed to the efficiency of oil
burning boilers so that less fossil fuels are consumed to maintain
a cleaner, healthier tomorrow.
Thermal management of a PEMFC with air cooling. NEVILLE PERKINS (Farmingdale State University, Farmingdale, NY, 11735)
DEVINDER MAHAJAN (Brookhaven National Laboratory, Upton, NY, 11973)
The use of
fossil fuel has become a major problem that has national security
implications and environmental concerns. The emission of green
house gasses and the need for clean renewable energy has led
to the research into alternative energy sources. One of the
options to replace fossil fuels is hydrogen fuel that can be
utilized in a PEMFC. The PEMFC produces heat energy as a byproduct
of the chemical reaction needed to produce electrical energy.
The removal of excess heat produced at a rate that keeps the
internal temperature constant at about 80ºC is a challenge.
Monitoring and controlling the external temperature of the
active area of the flow field at the bipolar plate or end plate
can be an economic way to keep the fuel cell within an ideal
temperature range. In this project, an array of 15 thermocouples
was dispersed across three bipolar plates in a fuel cell stack
to monitor the internal temperature and the rate of heat production.
An infrared heat sensing camera was also used to display the
external surface temperature of an operating fuel cell. The
output from the sixteen 15 thermocouples were connected to
data acquisition software. Real-time temperature monitoring
was automatically performed at predetermined time intervals.
Two fans with variable air flow were used to introduce a steady
stream of air to cool the external surface of the fuel cell
stack. Two other sensors were used to measure temperatures
up and down stream of the air flow used to cool the fuel cell.
Data was collected with the fuel cell stack operating at various
power levels while establishing the air flow required to keep
the internal fuel cell temperature constant at safe operating
level. The heat generated by the power stack spikes and causes
hot spots during periods of high demand, requiring effective
cooling. It is inferred from the collected data that an economical
air-cooling system could be designed for a fuel cell stack
that would allow it to operate under isothermal conditions.
Finding a relationship between active area, heat produced,
and air flow required to remove excess heat can supply the
design tool needed to configure the cooling system for any
fuel cell size.
Three Dimensional Environment Models for Electromagnetic Wave Simulation. TOMAS TINOCO (Diablo Valley College, Pleasant Hill,
CA, 94523) JAMES NUTARO (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Accurate electromagnetic
wave simulation demands accurate models of the environment. New
techniques that combine ideas proposed by Christiaan Huygens,
transmission line theory, and the powerful capabilities of today’s
computers, could allow fast, accurate and large scale electromagnetic
wave simulations. These techniques require three dimensional
models with information of the material properties at each point
in space to calculate the speed of wave propagation as well as
the reflection and transmission coefficients. Therefore, such
techniques can not be applied unless models with the necessary
information are provided. To address this problem and create
the required models, elevation data from the United States Geological
Survey (USGS) was used for modeling terrain and Virtual Reality
Modeling Language (VRML) was used for modeling buildings. From
USGS files, information was extracted to determine the elevation
points of a specific region. Subsequently, interpolation techniques
were used to obtain the required resolution and a three dimensional
array was allocated to store the properties of each point in
space. For modeling buildings, VRML files were used as input
to a conversion software that stored the physical properties
of each location based on the VRML shapes present and their specifications.
Using these methods, two models were created; one model using
USGS elevation data for Bethel Valley and the other from a VRML
model of Oak Ridge National Laboratory courtyard. The terrain
model had one meter resolution and contained material properties
at each location but was limited to two types of materials. On
the other hand, the courtyard model was based on basic shapes
but contained the required resolution and a greater variety of
material types. This work allowed the creation of the necessary
three dimensional models of the environment with the required
information and resolution for testing an electromagnetic wave
simulator. It was possible to execute the simulation in these
models to analyze the time and memory efficiency and to find
ways to increase the speed of simulation. Lastly, the courtyard
model was used to simulate the path loss of a radio signal and
the results were in agreement with measurements taken at different
locations of the model. Based on the difference between simulated
and measured values, the research team can increase the level
of details of the model to improve the results produced by the
simulator.
Transportable Radiation Monitoring Systems. JULIA MOLINE
(Columbia University, New York, NY, 10027)
PAT HU (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Malevolent
use of radioactive material poses a great threat to US national
security. As part of U.S. Department of Homeland Security’s initiative
to address threats of transporting illicit radioactive materials
on the national transportation network, the Oak Ridge National
Laboratory (ORNL) is designing and testing a Transportable Radiation
Monitoring System (TRMS). TRMS is a set of radionuclide detectors
that could be set up at truck stops, rest areas, or on either
side of a road to monitor vehicles passing through. The development
of the TRMS will allow authorities to deploy radionuclide detectors
to any site through which they believe illicit radioactive material
may be traveling. It will also facilitate the necessary communication
between local, state, and federal law enforcement agencies in
the event that something illicit is detected. In May and June,
2006, the TRMS was tested at three sites on the grounds of ORNL.
Its accuracy and efficiency were measured by observing its operational
efficiency (e.g., recorded down-times) and by comparing the data
the system recorded with information on shipments of radioactive
material, which were provided by the ORNL Shipping Department.
The data were analyzed by a number of variables, including the
radionuclides carried by monitored vehicles, speed of vehicles
going through the TRMS, and weather conditions at the test sites.
Based on conclusions drawn from a series of statistical analyses
on the data, the system and the procedures used to operate it
will be improved. After the preliminary analysis of the TRMS
tests is complete, the system will be tested at various sites
on interstates in the Southeast. The challenges of these field
tests include not only the technical aspects of the system (accuracy
of the alarms, data collection, etc.) but organizational issues
having to do with the necessary involvement of various government
agencies in any deployment of the TRMS.
Uncertainty of Available Energy and Available Power. SHAWN
ALLRED (University of Wyoming, Laramie, WY, 82070) JON CHRISTOPHERSEN (Idaho National Laboratory, Idaho
Falls, ID, 83415)
Documenting
the uncertainty analysis of the derived parameters grouped as
Available Energy (AE) and Available Power (AP) for battery cells
is a very complex problem. The error is an unknown combination
of both linearity and offset; the analysis computes the uncertainty
both ways and then the most conservative method is used (which
is the worst case scenario). Each method requires the use of
over 134 equations, some of which are derived and some are measured
values. This includes the measurement device error (calibration
error) and bit resolution and analog noise error (standard deviation
error). The implementation of these equations to acquire a closed
form answer was done using Matlab (an array based programming
language). The uncertainty is automatically computed and will
become part of the reported results for future battery testing.
Upgrade of Insertion Device Magnetic Measurement System: Motion Control and
Position Measurement. JUSTIN HSU (University
of California, Berkeley, Berkeley, CA, 94720) STEVE MARKS (Lawrence Berkeley
National Laboratory, Berkley, CA, 94720)
An Elliptically
Polarizing Undulator (EPU) is a storage ring insertion device
that generates intense light for use in scientific experiments
at synchrotron radiation facilities like the Advanced Light Source
(ALS). An EPU has four individual mechanical beams, which are
comprised of permanent magnets that have been arranged in a deliberate
pattern of alternating pole orientations. By adjusting the position
of the beams, one is able to manipulate the trajectory of an
electron beam into a sinusoidal or helical path, inducing a desirable
phase-coherent superposition that increases the intensity of
the produced light by many orders of magnitude. Because the electron
beam path depends directly on the EPU’s magnetic field, errors
in the magnetic field translate into out-of-phase beam trajectories,
leading to degradation in brightness. To prevent this, a precision
magnetic measurement system is used to measure magnetic field
as a function of position. This device assesses optical phase
errors and provides a basis for correcting the EPU’s magnetic
field. Because it had been several years since the magnetic measurement
bench at the ALS had been upgraded, many of the components were
obsolete. In order to maintain compatibility with newer equipment
and software, a complete overhaul of the device was necessary.
My task involved upgrading key components of the system. This
included replacing laser interferometers with linear encoders,
mechanical mounting of the linear encoders, installing an updated
motor controller, building a convenient user interface to display
all data, planning/implementation of the system’s electrical
wiring, updating the computer’s software/operating system, and
writing C/C++ code that facilitated communication within the
entire system. Because the project is still ongoing, experimental
results have yet to be determined. Future work may involve further
investigation and code modification to expand system functionality.
Usability Improvements to Existing Detection Equipment. FRANKIE
PONTILLO (Purdue University, West Lafayette, IN, 47906) YOUNG
SOO PARK (Argonne National Laboratory, Argonne, IL, 60439)
The goal
of the project was to develop specific improvements in the
method, techniques, and equipment to allow better usability
of existing radiation search equipment in the field. A number
of hand-held detectors were inspected. The objective was to
develop concepts for hands-free operation for each of the detectors
These devices include the Indentifinder, a medium weight and
sized device that detects radio nuclides, the SAM-935, that
is a special nuclear material detector larger in weight and
size than the previous, the UDR, a handheld radioactive device
that is small in size and weight and often used in the military,
and the ORTEC Detective, a gamma-ray detector that is bulky
in size and weighs a lot. These devices are very important
both inside and outside Argonne National Laboratory. It was
important to become familiar with the equipment and with the
previous and alternative ideas used. Searching the internet,
reviewing books, and visiting manufacturer websites, especially
for these devices that we were working with, helped in developing
our initial ideas of improving the devices. Looking at devices
that were already marketed, but not necessarily ones that served
a purpose to the radioactive search devices, shed light on
our current situation and gave an idea for designing hands-free
devices. Getting contact with companies and putting ideas into
visuals that could be presented seemed to get the project moving
in the right direction. For the UDR the device design was similar
to the iPod neoprene cases, with some slight modifications.
For the Identifinder a retractable locking clip device, was
used that could be purchased on the open market. For the SAM-935
ideas were taken from a car mounted DVD case, and modified
to be part of a pack system that could hold the device. Lastly,
for the ORTEC there is a need to come up with an idea for a
way to carry the device as a front and back pack, but still
be accessible. We are currently having ideas turned into prototypes,
with respect to the future of this project; the main goal is
that the prototypes be successful to the radioactive search
industries. New casing designs were used successfully with
the commercial radioactive devices. These new casings with
respect to the old ones are more durable, easier to use, and
make transportation of the radioactive detectors easier.
Validating Computational Fluid Dynamics Simulations of Thermodynamic Flow in
the Very High Temperature Reactor Lower Plenum. MARY SPROUSE
(Kansas State University, Manhattan, KS, 66506) W.D. POINTER
(Argonne National Laboratory, Argonne, IL, 60439)
The Generation
IV International Forum (GIF) has been organized to address
future energy needs using nuclear energy systems. The Very
High Temperature Reactor (VHTR) is an advanced reactor concept
undergoing engineering development. The thermohydraulics of
the reactor must be modeled to ensure inherent safety in design.
Engineering simulations are carried out by using computational
fluid dynamics (CFD) software; CFD solves the conservation
equations (mass, momentum, and energy) to predict the behavior
of fluids in motion through a defined configuration. The software
enables a number of turbulence models to be chosen to assess,
for instance, the sensitivity of the nuclear system's thermohydraulics
to a specific model. The objective of this project was to investigate
the capabilities of the CFD package STAR-CD with respect to
coarse-to-fine meshing options and turbulence models, with
a focus on thermohydraulic flow in the lower plenum of the
VHTR. The potential thermal fatigue of the lower plenum structure,
as a result of poor thermal mixing, is expected to be the first
standard benchmark problem proposed by the GIF VHTR Methods
Project Management Board. In order to establish validity of
the turbulent flow CFD approach, steady and unsteady simulations
were run with various meshing options for a well-documented
reference tube bank experiment. The simulation results were
compared to experimental data generated by the Idaho National
Laboratory's matched index-of-refraction flow experiment to
evaluate the capability and packaged options (i.e., turbulence
models) of the STAR-CD simulation software. To date the simulations
have been found to correctly represent experimental trends.
However, differences appear between the coarse-to-fine meshing
approach relative to the experiment trends, in particular,
between the normalized velocity over distances on the simulated
reference tube bank. These differences are now being analyzed.
In addition, in order to model the VHTR lower plenum, a script
was developed that builds the representative geometry. Future
work includes running simulations for this model and comparing
the simulated and experimental data. These planned validation
exercises using STAR-CD will contribute to the design engineering
and safety analysis of advanced nuclear systems.
Validation of CFD Code for Heavy-Vehicle External Aerodynamics Simulation. EMILY DRINGENBERG (Kansas State University, Manhattan,
KS, 66502) W.D. POINTER (Argonne National Laboratory, Argonne,
IL, 60439)
Argonne National
Laboratory is using the computational fluid dynamics software
STAR-CD and its ES-AERO enhancement (both Adapco) to solve
the mass and momentum conservation equations as applied to
the generic conventional model of a tractor-trailer vehicle.
Preliminary studies show that a reduction in drag as small
as 5% translates to fuel savings of about 2.5%, which can be
as much as 500-1000 liters/year (~132-264 gal/year) for 150,000
km (~93,206 mi) annual highway driving for a single commercial
long-haul tractor-trailer vehicle. The STAR-CD program numerically
solves the turbulent flow around a tractor-trailer configuration
for different turbulent flow models and under various conditions.
By running simulations, information such as the coefficient
of drag and pressure distribution around the vehicle is revealed.
Both metrics are linked to the aerodynamic performance and
hence the fuel-efficiency of the tractor-trailer. Since one
defining variable of drag and pressure is the yaw, or the angle
at which the flow moving over the vehicle's surface encounters
the centerline of the vehicle, simulations are being carried
out at yaw angles 0°, 3°(or 2.5° when 3° is problematic), and
6°. Simulations were also conducted to model underhood air
flow with a standard radiator (as this is more realistic) and
since it influences the overall aerodynamic performance. The
information gathered from the simulations is compared to experimental
data collected from a scaled tractor-trailer experiment in
a wind tunnel. Major results showed an error of only ~12% for
the baseline geometry at all tested yaw which confirms the
ability of STAR-CD to be used in similar applications to predict
fluid flow. The V2F model suggested that for larger yaw angles,
a more advanced turbulence model may be needed. The side drag
and lift are typically difficult to predict but showed some
tendency to follow the trend for small yaw angles. The differences
and similarities resulting from this comparison have aided
in determining the usefulness and accuracy of the STAR-CD and
ES-AERO software as well as potential gains in fuel economy
for the tractor-trailer.
VDT’s Application to Hazmat Transportation. BRYCE
HUDEY (University of South
Florida, Tampa, Fl, 33620) BILL KNEE (Oak
Ridge National Laboratory, Oak
Ridge, TN, 37831)
The Transportation
Security Administration (TSA) has a goal of minimizing the
threat of domestic terrorism in the United States. Efforts
associated with this goal involve the consideration of Hazardous
Material (Hazmat) shipments and their potential use in terrorist
activities. Their volatile cargos can prove extremely lethal
if vehicle control is forfeited to a malicious individual.
The technological ability to prevent and/or minimize the operation
of a truck by an unauthorized individual is termed Vehicle
Disabling Technology (VDT). Recently, in a House of Representatives
Conference Report, testing and evaluation of VDTs to assess
their contribution to safety and security of Hazmat carriers
was endorsed. It was suggested that testing and evaluation
of VDTs be conducted by the Federal Motor Carrier Safety Administration
(FMCSA) and ORNL in order to generate “best practices” for
the use of such technologies in the Hazmat transport industry.
Initial efforts involved the identification of fourteen vendors
in North America that provide one or more VDT functional requirements:
vehicle disablement if the vehicle senses an unauthorized driver,
vehicle disablement in the event of a loss of signal, remote
vehicle disablement by the driver, the dispatcher, or law enforcement.
VDTs identified spanned relatively simple lockout devices which
prevented a truck from being started or would not disengage
the brakes, to technologies which would provide safe remote
shutdown of a vehicle even when traveling at highway speeds.
Information about the VDTs was gathered via a questionnaire,
and telephone conversations. Visits with the vendors are planned
in addition to gathering data from customers of the VDT vendors.
A review of “best practices” documents led to the development
of a “best practices” outline which will be utilized as a basis
for discussions with VDT vendors and vendor customers. Vendor-based
demonstrations of the technologies mounted on vendor-owned
vehicle platforms will also be provided. Additional data will
be gathered through visits to vendor owned laboratories, and
independent laboratory testing at ORNL. The data gathered from
demonstrations, tests and questionnaires, in addition to feedback
provided by Hazmat safety and security stakeholders will provide
the foundation for the primary result of this study, a “best
practices” document.
Verification and Application of a Thermosiphon Solar Water Heater Model. JAY JOHNSON (University of Missouri - Rolla, Rolla, MO, 65409)
JAY BURCH (National Renewable Energy Laboratory, Golden, CO,
89401)
Rising energy
prices and global warming have sparked added interest in wind,
biomass and solar technologies. Solar water heating can reduce
domestic water heating costs by more than half and currently
new Solar Domestic Hot Water (SDHW) systems are in development
and production. Thermosiphon systems are a relatively mature
technology, but there are still a number of uncertainties their
behavior. Thermosiphon systems use the natural buoyancy of
hot water to drive flow during the day, but at night cooler
ambient conditions cause reverse thermosiphoning. The National
Renewable Energy Laboratory (NREL) has developed a new model
using TRNSYS software, which can smoothly transition between
forward and reverse flows. Two of the new NREL components in
this model were verified by comparing analytical results to
the TRNSYS solution. Then using this model, reverse thermosiphoning
was studied and quantified in different climates and loop geometries
to understand the energy penalty of the typically ignored reverse
thermosiphoning phenomenon. New passive solar thermal systems
have the tank nearly coincident with the collector, so the
penalty from reverse thermosiphoning was of particular interest.
All modeling showed some level of reverse thermosiphoning regardless
of climate or tank position. Although these systems are highly
dependant on hot water draws, the reverse thermosiphon mass
was nine times larger in low tank configurations, forward thermosiphon
mass was 80% larger with the high tank configuration and hence
the high tank configuration was capable of delivering 25% more
energy annually than the low tank configuration. This points
to using systems with high tank configurations, but attic limitations
and the inconvenience of tank mounting may not always make
such geometry feasible. This work quantifies the penalty and
shows that such configurations, though not optimal, produce
reasonable savings.
Vulnerability Assessment of Major Dams Subjected to Large Transient Loads using
Finite Element Analysis. DONALD TEMPINSON (Southern Illinois University Carbondale, Carbondale,
IL, 62254) DR. NIKOLAOS SIMOS (Brookhaven National Laboratory,
Upton, NY, 11973)
The vulnerability
of major dams subjected to large transient loads is unknown
since these loads were not considered during the design process
of the dams. Due to the proprietary nature of the data in
relation to dams, exact results cannot be shared. The complexity
of these loads, in addition to the unique geometric and material
properties of a dam, make it extremely difficult to assess
a dam’s vulnerability. To overcome this obstacle, state of
the art computational techniques such as finite element analysis
must be utilized to assess the vulnerability of dams to these
large transient loads. Use of a general finite element analysis
program, ANSYS, allows the modeling of complex structures
and loads. In order to construct these models, information
is gathered from various sources such as structural plans
and research papers about related engineering problems. Basic
analyses of simplified models are run to determine which
dams are more vulnerable and require further detailed study.
The results from the detailed studies will reveal possible
weaknesses and allowed corrective measures to be taken to
secure the structure against this type of loading.
