NO{sub x} and N{sub 2}O in lean-premixed jet-stirred flames

Journal Article · Wed Feb 01 04:00:00 EST 1995 · Combustion and Flame

DOI:https://doi.org/10.1016/0010-2180(94)00070-9· OSTI ID:28061

Steele, R C; Malte, P C; Nicol, D G; Kramlich, J C ^[1]

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1. Univ. of Washington, Seattle, WA (United States). Combustion Labs.

This study examines NO{sub x}/N{sub 2}O formation mechanisms that are relevant to lean-premixed combustion in practical high-intensity combustors. Both experiments and kinetic modeling are presented. The experimental system for examining high-intensity, lean-premixed combustion is a 1-atm jet-stirred reactor. The reactor burns CH{sub 4} and CO/H{sub 2} over a fuel-air equivalence range of 0.41 to 0.67, a reactor mean residence time of 1.7--7.4 ms,and measured reactor temperature of 1,415 to 1,845 K. The CO/H{sub 2} fuel is used to eliminate the effects of hydrocarbon attack on the nitrogen system. The NO{sub x} mole fraction (wet) measured for the CH{sub 4} experiments correlates well with measured temperature (K) and reactor mean residence time {tau} (s) as follows: X{sub NO{sub x}} = {tau}(1.28 {times} 10{sup 4})exp({minus}27230/T). Because of the enhanced O-atom concentration, the NO{sub x} mole fraction for the Co/H{sub 2} combustion is about threefold higher than for the CH{sub 4} combustion. Furthermore, because the free radical behavior in the CO/H{sub 2} experiments is complex near blowout, a simple correlation is not available. For the CH{sub 4}-air experiments, chemical reactor modeling indicates that the approximate percentages of NO{sub x} production by the nitrous oxide, Zeldovich, and prompt mechanisms vary from 65:25:10 at 1,650 K to 35:50:15 at 1,850 K. For the Co/H{sub 2}-air experiments the nitrous oxide to Zeldovich contributions vary from 95:5 at 1,500 K to 65:35 at 1,725 K.

• OSTI ID: 28061
• Report Number(s): CONF-940711--
• Journal Information: Combustion and Flame, Journal Name: Combustion and Flame Journal Issue: 3 Vol. 100; ISSN CBFMAO; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

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KINETIC EQUATIONS
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