Performance study of an induced air porous radiant burner for household applications at high altitude

• A performance study of an induced air porous radiant burner was carried out.
• Thermal and radiation efficiencies were measured for a porous radiant burner.
• CO and NOx emission levels were measured for a porous radiant burner.
• A maximum porous burner thermal efficiency near 50% was obtained for 370 kW/m2.

Porous radiant burners are presented as an alternative technology for improving the thermal efficiency of conventional burners. A performance study of an induced air porous radiant burner (IAPRB) with submerged combustion using natural gas was performed at high altitude to assess the feasibility of employing a porous burner operated with induced air in household applications. The experiments were performed in two-layer porous media. The preheating and combustion zones consisted of 400 ppi alumina honeycomb and 90% porosity silicon carbide foam, respectively. Three power per unit area levels, 370 kW/m2, 480 kW/m2 and 670 kW/m2, were evaluated. Pollutant emissions (CO and NOx), the radiation efficiency, the temperature profile along the bed, the primary air rate and the pressure drop across the porous materials were measured. A maximum burner thermal efficiency near 50% was obtained for 370 kW/m2, with a radiation efficiency of 27%. The preheating of the premix caused an increased bed pressure drop, which resulted in a reduction in ambient air entrainment and an air deficiency in the reaction zone. The CO emissions exceeded the standard allowable emissions.