Effect of Porous Foam Material on Combustion Characteristics of a Natural-draft Radiant Burner Fueled by Gasohol E85

This research is to develop a natural-draft, fuel-flexible, radiant burner for application in light-duty heating processes. It can be used for both LPG cooking gas and alcohol-containing fuel. Nevertheless, ethanol has a low calorific value compared to LPG gas. Therefore, super adiabatic combustion (SAC) technology is applied by using a porous material burner in order to create internal heat recirculation. The combustion temperature is higher than that of conventional combustion because the incoming fuel-air mixture was preheated automatically. The most popular porous material today is the ceramic foam type because of its lightweight and high porosity, thus, it shortens the ignition time and quickly reaches equilibrium. However, there are a variety of materials used to make foam ceramics that have different thermal properties, which will affect combustion characteristics and heat transfer. Therefore, this research aims to study and compare the properties of various types of foam ceramic burners, including the thickness of the porous materials that affect the burner's performance. The combustion characteristics of the burners equipped with 3 types of porous materials, namely aluminum oxide, silicon carbide, and zirconia with a porosity of 10 PPI were compared. The results showed that combustion with gasohol E85 fuel was very stable in all tested burners. The installation of double porous materials produced a higher combustion temperature and lower CO emissions than the one layer. Because the double porous material promotes a higher degree of heat circulation. Combustion in zirconia produces a maximum combustion temperature of over 910 ^oC at 5.7 kW, while a silicon carbide has the lowest temperature. This also results in the lowest CO emissions from combustion in zirconia foam among the tested foam.