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The laminar burning velocities of a stoichiometric CH4–N2O mixture diluted with N2 [30–60% (by volume)] at various initial pressures (1–10 bar) and various initial temperatures (273.15–423 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 N2 concentration) of CH4–N2O–N2 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 CH4–N2O oxidation are determined. [ABSTRACT FROM AUTHOR]

Flame propagation was studied in methane-air-inert (He, Ar, N 2 or CO 2 ) mixtures with various initial pressures and compositions using pressure-time records obtained in a spherical vessel with central ignition. The laminar burning velocities of CH 4 -air and CH 4 -air-inert mixtures obtained from experimental p(t) records of the early stage of combustion were compared with literature data and with those obtained from numerical modeling of 1D flames. The overall reaction orders of methane oxidation were determined from the baric coefficients of the laminar burning velocities determined from power-law equations. For all mixtures, the adiabatic flames temperatures were computed, assuming that the chemical equilibrium is reached in the flame front. The overall activation energy for the propagation stage of the combustion process was determined from the temperature dependence of the laminar burning velocity., (Copyright © 2016 Elsevier B.V. All rights reserved.)