Thermodynamic analysis of a novel combined cooling and power system driven by low-grade heat sources

Abstract

A novel combined cooling and power system which combines a conventional ammonia-water power/cooling cycle named Goswami cycle and an ejector refrigeration cycle is proposed and investigated. This new combined system can improve the refrigerating capacity of the conventional power/cooling system, and it can also adjust the cooling capacity to power ratio by changing the proportion of the ammonia-water flow into the turbine and the ejector. A mathematical model is developed to study the system performance. It is shown that under the given conditions the combined thermal efficiency and the combined exergy efficiency are 17.49% and 26.15%, respectively. The exergy analysis shows that the exergy destruction mainly occurs in the recovery heat exchanger, followed by boiler and rectifier, respectively. Parametric study shows that the absorber temperature, the cycle highest pressure and low pressure, the boiler temperature and the split ratio have significant effects on the net work output, the cooling capacity, the combined thermal efficiency and the combined exergy efficiency.