Premixed Carbon Monoxide-Nitrous Oxide-Hydrogen Flames: Measured and Calculated Burning Velocities With and Without Fe(CO)5.
Premixed Carbon Monoxide-Nitrous Oxide-Hydrogen Flames:
Measured and Calculated Burning Velocities With and
Without Fe(CO)5.
(214 K)
Linteris, G. T.; Rumminger, M. D.; Babushok, V. I.
NISTIR 6374; 39 p. October 1999.
Combustion and Flame, Vol. 120, No. 1/2, 58-75, 2000.
Available from:
National Technical Information Service
(NTIS), Technology Administration, U.S. Department of
Commerce, Springfield, VA 22161.
Telephone:
1-800-553-6847 or 703-605-6000;
Fax: 703-605-6900.
Website: http://www.ntis.gov
Order number: PB2000-100436
Keywords:
carbon monoxide; chemical inhibition; flame chemistry;
iron pentacarbonyl; nitrous oxides; promoters;
propellants
Abstract:
The burning velocity of premixed carbon monoxide-nitrous
oxide flames (background water levels of 5 to 15 ppm)
has been determined experimentally for a range of
fuel-oxidizer equivalence ratio phi from 0.6 to 3.2,
with added nitrogen up to a mole fraction of XN2 = 0.25,
and with hydrogen added up to XH2 = 0.005. Numerical
modeling of the flames based on a recently developed
kinetic mechanism predicts the burning velocity
reasonably well, and indicates that the direct reaction
of CO with N20 is the most important reaction for CO and
N20 consumption for values of XH2 < 0.0014. The
calculations show that a background H2 level of 10 ppm
increases the burning velocity by only about 1% compared
to the bone-dry case. Addition of iron pentacarbonyl,
Fe(CO)5, a powerful flame inhibitor in hydrocarbon-air
flames, increases the burning velocity of the CO-N20
flames significantly. The promotion is believed to be
due to the iron-catalyzed gas-phase reaction of N20 with
CO, via N20 + M = N2 + MO and CO+ MO = CO2 + M, where M
is Fe, FeO, or FeOH.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899