Improvement in specific power of stirling engine by using a new heat exchanger

The performance of a Stirling engine depends significantly on performance of heat exchanger. The heat exchanger of a Stirling engine comprises a heater, a cooler, and a regenerator. The heater and cooler perform heat transferring from high and low external heat sources to working gas, while the regenerator absorbs heat from the working gas when the gas flows from heater to cooler and releases heat during the reverse process. These auxiliary devices increase the weight of the engine and reduce its specific power. In this study, in order to improve the performance of the compact Stirling engine, a new heat exchanger (hereafter called the prototype heat exchanger) with a heater that reduces the energy loss from combustion gas, and a cooling system that uses fuel gas were developed. The performances of these systems were then compared with that of a conventional multi-tube heat exchanger. The prototype heat exchanger capable of reducing the heat loss in a heat exchanger via conbusting in a tube. Additionally, the weight of the prototype heat exchanger is lighter than that of a conventional multi-tube heat exchanger. The prototype heat exchanger is advantageous for reducing the engine weight and improving the specific power. Experiments conducted on the prototype heat exchanger installed on the engine showed excellent results and its superior performance.