Design method and the development of the low-temperature-difference indirect heating Stirling engine

Abstract

Low-temperature-difference indirect heating Stirling engine is the most suitable device for a small-scale wood biomass combined heat and power. To design this type of Stirling engine, conventional design method is not sufficient for optimizing working space temperature difference. Therefore, a new design method is developed. A ratio of working gas displacement to volume change is defined, which is found to be a simple function related to the temperature ratio of the ideal Stirling cycle. Through the preliminary study, it is found that the conventional alpha, beta and gamma Stirling engines are not suitable for practical low-temperature-difference engines. Finally, alpha-plus-type engine which is optimized for low temperature difference operation is proposed. The new engine is developed and the results of the operation test is demonstrated.

Keywords

• stirling engine
• combined heat and power
• design method
• biomass