numerical simulation of porous radiant burners under transient condition

The purpose of this work is to analyze two dimensional rectangular porous radiant burners for investigating the thermal characteristics of this type of burners in starting time period. since, the solid and gas phases are not in thermal equilibrium, two separate energy equations for these two phases are solved numerically with alternative direction implicit scheme. the gas is considered nonradiative medium and for computation of radiative heat flux through the solid phase, the radiative transfer equation (rte) is employed and solved with the discrete ordinates method (dom). it is obtained that due to the dominant radiation effects, the required time to reach the steady gas temperature is very low. furthermore, the effects of optical thickness and scattering albedo on the performance of porous radiant burner (prb) are investigated.