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Abstract: The indirect chemical effects of fuel dilution by CO₂ on NO formation were investigated numerically in this paper. CH₄ doped with NH₃ was used as fuel, while CO₂ and O₂ were mixed as oxidant. The dilution effect of CO₂ was then investigated through adding extra CO₂ to the reaction system. An isothermal plug flow reactor was used. An unbranched chain reaction mechanism is proposed to illustrate the chemical effects of CO₂ on the H/O/OH radical pool and NO_x. Due to the reaction between CO₂ and H, extra NO will be formed in fuel-rich conditions, while NO will be inhibited in fuel-lean conditions and high CO₂ dilution conditions. The reaction affected the radical pools of OH, H, and O of the branched chain reaction, and then the formation and reduction of NO. The pool of H had the greatest effect on NO reduction. The results suggest that the indirect chemical effects on NO formation differ between diluted fuel oxy-fuel combustion conditions and NOrmal oxy-fuel conditions.

This paper reports on a computational study of the influence of CO2 dilution and reaction on the formation and reduction of NO generated from CH4 doped with NH3 (to simulate fuel-bound N).The area of study is of great importance to the combustion and energy community.

模拟富氧燃烧过程中燃料在CO₂中稀释对NH₃向NO_x转化影响的研究

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