Parametric Studies of Thermal Efficiency in a Proposed Porous Radiant Recirculated Burner (PRRB): A Design Concept for the Future Burner

Abstract

The present study proposes a new design for a gas burner in order to improve the thermal efficiency of conventional open-flame atmospheric burners which are now widely used in most domestic appliances. The study proposes an efficient means for improving the thermal efficiency of the burners by ultilizing a porous medium technology. An internal heat recirculation system was constructed in order to capture and recirculate some of the enthalpy of the exhaust gas. A porous medium of an appropriate optical thickness was used, based on the principal that the porous medium will convert the enthalpy of the exhaust gases to thermal radiation which is then fed back to the burner inlet. The experimental results show that the porous medium was very effective in increasing the thermal efficiency due to the efficiency of the internal heat recirculation taking place in the burner. The first-law thermal efficiency of the proposed porous radiant recirculated burner (PRRB), is on an average approximately 10 % higher than those of the standard burner (SB) and the porous radiant burner (PRB).