Combustion of CH4/O2/N2 in a well stirred reactor

Detailed kinetic calculations of chemical reactions using GRI-Mech 3.0 are carried out to characterize the combustion of CH4/O2/N2 mixture in a well-stirred reactor (WSR). Very wide ranges of the inlet temperature Tin (300 K-2700 K), nitrogen dilution concentration (0%-99%) and global equivalence ratio (0.5-4.0) are considered. The extinction and self-ignition temperatures (Tex and Tsi) of the CH4/O2/N2 mixture are identified by the ignition-extinction S-curve. Based on Tex, TsiTWSR, and the operative conditions (Tin and the mixture composition), the WSR combustion of CH4/O2/N2 can be quantitatively classified into several particular regimes. Moreover, the product composition and elementary chemical pathways of the CH4 oxidation are also examined. Results demonstrate that the WSR working temperature determines the chemical characteristics of the CH4 oxidation rather than the combustion regime.