A general model for two-stage vapor compression heat pump systems

作者:Jiang, Shuang; Wang, Shugang; Jin, Xu; Zhang, Tengfei*
来源:International Journal of Refrigeration, 2015, 51: 88-102.
DOI:10.1016/j.ijrefrig.2014.12.005

摘要

Two-stage vapor compression technology has high potential of performance improvement for cold climate heat pumps, and there are several types of inter-stage configurations that need to be evaluated before making a choice. A general model of these configurations is first derived from a subcooler cycle and then is extended to be capable of evaluating many other inter-stage configurations by employing an "input domain". The model is solved with a sequential algorithm and an analytical initial solution of the intermediate pressure is presented. After an experimentally validation with additional calculations of the sub-cooling parameter, the evaporating and condensing pressure, this general model is then used in the performance comparison and analysis of eight different inter-stage configurations. At last, case studies show that, this general model is capable of performing performance comparison among cycles with different types of inter-stage configurations, as well as refrigerant selection and operational analysis.