From allspach@fnal.gov Mon Aug 11 12:22:07 2003
Date: Fri, 08 Aug 2003 16:09:01 -0500
From: Del Allspach <allspach@fnal.gov>
To: baller@fnal.gov
Subject: Numi Air System Review Comments

Bruce,
These are my comments from the Numi Air System Review:

The engineering and design team has done a very thorough job in
analyzing this system.  The calculations performed are appropriate and
well thought out.

1.	Regarding the flow calculations, it is important that all of the
characteristics of the system be well understood and correctly applied
in the calculations, however, one should keep in mind that the formulas
used will only provide answers to roughly +/-15%. A check of the
calculations with FEA would be prudent, but in the end, specifying a fan
(for continuous operation) that will be able to provide the required
flow with a pressure head at 10 or 15 % higher than that calculated
would be advised.

2.	Given the size of the fan and the space available, it may not be
practical to have an installed spare in parallel. In this case, simply
having spare parts for the installed fan would be advisable. Performing
regular checks during available downtimes could also be planned.

3.	Although 55 F seems to be the lowest temperature at which the
air cooling system would need to maintain the concrete blocks, it would
be interesting for the team to request from the manufacturer a chart
showing how the cooling capacity of the system would decrease if the set
point temperature were adjusted lower and vice versa, increase if it
were raised. This could help to understand what contingency is offered
by the cooling system. It is also interesting to note that changing the
set point for the humidity will also have an effect on the available
cooling capacity. Operating at the upper end of the acceptable humidity
range would increase the cooling capacity. After understanding the
effects of these variables, specifying a contingency on the cooling
capacity would be advisable.

4.	The system seems to be well instrumented.

5.	The alarming on the filtering system is a good idea. Multiple
levels of alarming could be implemented. Can the filters be changed
while the system is running?  Should a bypass duct be in place for this
purpose?


Del Allspach