Towards the development of a high power density, high efficiency, micro power generator

An innovative method to use combustion-based source for portable power generation for Microelectromechanical systems with significant improvement in power density and conversion efficiency has been reported in this study. A triple microcombustor configuration with backward facing steps and associated provision for efficient heat recirculation is proposed for flame stabilization. The presence of three parallel combustion zones increases the combustion intensity compared to a single combustor configuration and enhances the overall thermal performance. A novel technique to extract maximum heat from the hot combustion products for thermoelectric power generation is implemented. The thermoelectric modules are mounted to facilitate direct contact of the module surface with the hot combustion products. A significant improvement in heat transfer rate from the hot combustion gases to the thermoelectric modules (~16 times) is achieved. An electric power output of 4.9 W with overall conversion efficieny of 5.09% at a mixture velocity of 10 m/s and a mixture equivalence ratio of 0.9 is achieved. This signifies an improvement of ~10–20% in overall conversion efficiency as compared to previously reported systems.