Numerical study of laminar flame propagation in $\mathrm{CH}_4$–$\mathrm{N}_2\mathrm{O}$–$\mathrm{N}_2$ at moderate pressures and temperatures

The laminar burning velocities of a stoichiometric $\mathrm{CH}_4$–$\mathrm{N}_2\mathrm{O}$ mixture diluted with $\mathrm{N}_2$ [$30\div60\%$ (by volume)] at various initial pressures ($1\div10$ bar) and various initial temperatures ($273\div423$ K) are obtained by numerical modelling of their premixed adiabatic flames. The modelling is performed with the Cosilab package using the GRI-Mech 3.0 mechanism based on $53$ chemical species and $325$ elementary reactions. The calculated laminar burning velocities are compared with available literature data. The influence of the initial conditions (pressure, temperature, and $\mathrm{N}_2$ concentration) of $\mathrm{CH}_4$–$\mathrm{N}_2\mathrm{O}$–$\mathrm{N}_2$ mixtures on the laminar burning velocities, maximum flame temperature, heat release rate, and peak concentrations of the main reaction intermediates is investigated and discussed. Using the correlations of the laminar burning velocities with the initial pressure and the average flame temperature, the overall activation parameters of $\mathrm{CH}_4$–$\mathrm{N}_2\mathrm{O}$ oxidation are determined.