Radiation output efficiency and emissions in a porous burner

Combustion of CH4/Air premixed gases in a porous burner was simulated using the two-equation model and the detailed reaction mechanism GRI 3. 0. Preheat efficiency, radiation output efficiency and emission output were analyzed under different equivalence ratios and mass fluxes. Sensibility analysis of radiation output efficiency with thermophysical properties was also studied. The results show that radiation output efficiency increases with the increase of interphase heat exchange coefficient or the decrease of extinction coefficient, equivalence ratio or mass flux, and that emission output decreases with the decrease of equivalence ratio or mass flux. Of all the influencing factors, equivalence ratio is of the greatest importance. So developing ultra-lean combustion is the key to improving efficiency and decreasing emission of the porous burner.