Exergy assessment of heat transfer inside a Beta type Stirling engine

摘要

This paper presents an assessment of both energy and exergy efficiencies of a Beta Stirling engine prototype with a 30 W capacity as the maximum mechanical power output. Its operating pressure is close to atmospheric pressure, and it supports a maximum hot end temperature of 650 degrees C. The prototype is experimented with and without thermal insulation of its two heat sources. Exergy destructions are quantified and analysed, and their causes are explained. The effects of external losses and their reduction on energy and exergy efficiencies are investigated. Furthermore, the effects of rotational speed on the performances of the engine were investigated and their relations with temperature and pressure drop are illustrated.