Energetic and exergetic performance evaluations of an experimental beta type stirling machine

Abstract

This chapter focuses on a beta type Stirling receptive machine operatingunder an atmospheric pressure between two heat sources at constant temperatures.Two receiving modes are studied experimentally (refrigerator mode and heat pumpmode). Parameters such as hot end temperature (about 110 C maximum hottemperature output for the heat pump mode), cold end temperature (about32 C minimum cold temperature output for refrigerating mode) and coefficientof performance (COP) are studied under different engine speeds. In order to assessthe receptive Stirling machine, we carry out energy and exergy performanceassessment studies. Energetic and exergetic coefficients of performance and exergydestructions in the heat pump system and the refrigerating machine are quantified atdifferent engine speeds. The results show that optimal operating mode for refrigeratingmachine is obtained at about 155 rpm. But, around this speed the heat pumpmode deliver the worst COP. The influence of heat sources insulation on the exergy