Development of a Miniaturized Energy Converter Without Moving Parts

New developments in portable electrical and mechanical devices have created demand for increasing amounts of energy and thus new ways of supplying energy. The high energy density of hydrocarbon fuels are a possible way to solve this issue. This paper deals with the development of an adapted thermodynamic concept for a micro energy converter based on the thermoelectric effect. Developing a PowerMEMS device that does not contain any moving parts is the main design feature. In the proposed concept liquid hydrocarbon fuel, such as methanol, is evaporated in a micro evaporator, mixed with air, and combusted in a micro combustion chamber. The combustion process is assisted by catalytically coated microfibers. Electrical power can be generated by a thermoelectric generator, which is located between the hot combustion zone and the cold micro evaporator. This arrangement leads to large temperature differences between hot and cold junctions, which is necessary for efficient thermoelectric energy conversion and hence power generation. For a more detailed investigation of thermal boundary conditions and interior thermal management, in-situ temperature measurements of the combustor walls are performed using thermographic phosphors.