Specific features of combustion of hydrocarbon gases in composite porous inserts

Results of an experimental study of combustion of propane-butane and methane with air in inserts made of a porous material with a pore size of $\approx$ 0.35 mm and a cellularporous material with a pore size of $\approx$ 3 mm, with the combustion zone being located at the junction between the materials, are presented. A comparison of the composition of the products and combustion efficiency with results calculated for equilibrium compositions in the range of the air-to-fuel ratio $\alpha$ = 0.4–2.5 reveals significant deviations of the experimental data from the equilibrium values (lower fraction of H$_2$ and NO, a greater value of the ratio CO/CO$_2$, elevated combustion efficiency at $\alpha$ = 0.6–0.7, and reduced combustion efficiency in the stoichiometric region) caused by intense radiative heat removal and radiative quenching of the composition of combustion products.