Two-Dimensional Numerical Study of Methane-Air Combustion Within Catalytic and Non-catalytic Porous Medium

This study numerically investigates a two-dimensional physical model of methane/air mixture combustion in catalytic and non-catalytic porous media. The temperature distribution and flame stability of combustion in inert alumina (Al2O3) pellets and platinum (Pt) catalyst-supported alumina (Al2O3) pellets, were studied by changing the burner structure, operating parameters, and physical properties of alumina pellets. The simulation results indicated that the gas temperature in the inert porous medium is higher than that in a catalytic porous medium, while the solid temperature in an inert porous medium is lower than that in a catalytic porous medium. The flame moved toward the burner exit with the increasing diameter of the packed pellets at a lower equivalence ratio and moved toward upstream with the increased thermal conductivity of packed pellets. The flame location of the catalytic porous burner was more sensitive to the flame velocity and insensitive to thermal conductivity compared to the inert porous burner. The distance of the flame location to the burner inlet is almost constant with the increasing length of the porous media for both the catalytic and inert porous burner, while the relative position of the flame location moved toward the upstream.