Experimental and kinetic modeling study of NO formation in premixed CH4+O2+N2 flames

The nitric oxide (NO) formation in methane (CH4) flames has been widely investigated, with quite a few kinetic mechanisms available the literature. However, studies have shown that there are often discrepancies between simulations using various and experimental results. To elucidate reactions leading to these discrepancies, experiments were designed measure NO post flame zone of CH4+O2+N2 oxygen ratio, xO2 = O2/(O2+N2), varying from 0.2 0.27. carried out on heat flux burner at atmospheric pressure 298 K saturated Laser-induced fluorescence. equivalence ?, was changed 0.7 1.6. corresponding laminar burning velocity, SL, for each condition also measured method. A comparison made present data simulation results Konnov, Glarborg, NOMecha 2.0, San Diego mechanisms, none them well reproduced new all investigated conditions. Numerical analyses show increment mole fraction stoichiometric fuel-lean when increases is mostly defined by thermal-NO production, which found be over-predicted, especially Konnov mechanisms. rate constant reaction NO+N N2+O derived as k=1.529×1013T?0.0027exp(185.41[cal/mole]RT) cm3 / mol s over 225–2400 temperature range. constants four controlling CH profiles prompt-NO updated based analysis literature yields an improved performance mechanism.