Exergy analysis for quasi two-stage compression heat pump system coupled with ejector

Ejectors are simple mechanical components, can utilize high pressure energy from liquid in the quasi two-stage compression heat pump system coupled with scroll compressor, and the performance of the heat pump system can be further improved. According to thermal analysis model based on the first and second law of thermodynamics, the heat pump prototype has been developed and comprehensively tested, the influence of ejector on the heat pump system was exergetically analyzed using experimental data of the prototype. The results show that, compressor has the greatest exergy loss, amounts to about 77% of the total exergy; ejector can recover the fluid pressure exergy in supplementary circuit compared with the throttling element in the quasi two-stage compression heat pump system, decreases the exergy loss of compressor; and the exergetic efficiency can be improved about 3-5%, while the exergy output remains nearly constant.