Experimental study on the effect of material in the combustion zone on the performance of an LPG fuelled porous radiant burner

Abstract

The experimental study on the combustion of LPG/air was performed in a two-layer porous radiant burner (PRB) with different combustion zone (CZ) materials like alumina (Al2O3), zirconia (ZrO2), and silicon carbide (SiC) foam of 90% porosity keeping the preheat zone material fixed. The SiC provided stable combustion at the equivalence ratio (ϕ) of 0.55–0.70, whereas Al2O3 and ZrO2 provided stability at the ϕ of 0.61–0.86, and 0.59–0.84 respectively. The highest radiation efficiency is found to be 43.62%, 14.35%, and 12.73% for SiC, ZrO2, and Al2O3 respectively at the firing rate(P) of 200 kW/m2 and ϕ of 0.70. The variation in NOx emission is 3.6–4.9 ppm, 3–4.1 ppm, and 2.8–3.8 ppm for SiC, ZrO2, and Al2O3 respectively at the P of 200–400 kW/m2 and ϕ of 0.70. The ZrO2 and Al2O3 emitted higher CO of 73–93 ppm and 75–95 ppm respectively compared to the SiC of 62–82 ppm at the P of 200–400 kW/m2 and ϕ of 0.70. It has been observed that SiC as CZ has offered the highest radiation efficiency (43.62%), lowest CO (62–82 ppm), and slightly more NOX (3.6–4.9). Overall SiC is a better choice than ZrO2 and Al2O3 as CZ material for LPG fuelled two-layered PRB.