Experimental analysis of natural gas combustion in a porous burner

The study aims to evaluate a novel porous medium burner (PMB) with a heat exchanger for household heating systems. In this regard, a PMB together with a heat exchanger is designed and built in the laboratory. The changes of temperature in the porous medium combustion chamber have been recorded, and the pressure losses in the burner, thermal efficiency of the burner, and the concentration of NO polluting gasses have been measured. The obtained results indicate that the maximum temperature is at the beginning of the combustion zone and the end of the preheating zone; but, with the increase of power and the excess air ratio, the flame front moves forward. At a constant power, with the increase of the excess air ratio, the total flow rate increases, followed by the increase of pressure loss. The thermal efficiency results indicate that the highest efficiency is achieved at the excess air ratio of 1/2. This is due to the fact that at this ratio, the combustion products have their highest temperature. The volume of excess air has a significant influence on the amount of NO produced. With the increase of excess air, the volume of NO gasses diminishes.