CASCADE SYSTEM COMBINED BY SOLAR EJECTOR REFRIGERATION CYCLE AND CO_2 REFRIGERATION CYCLE

摘要

In this paper, a cascade system combined by a solar powered ejection cycle with a CO_2 vaporrncompression/ejection cycle is studied. The ejector is used as the main expansion device instead of the throttlernvalve in the CO_2 compression refrigeration cycle. The performance of the cascade system to cooling or heatingrnis analyzed and compared with the solar energy ejection refrigeration cycle. Then the energy-saving potentialrnis obtained during the cooling season by simulating the operation of the system under the actual weatherrnconditions of Tianjin in China. It is found that in the cooling season, the cascade system has a betterrnperformance than the ejection system when the solar collector area is small. During the cooling season, it canrnreduce the energy consumption by about 59% in comparison with that of a vapor compression cycle.rnKey words: Solar, Ejection system, CO_2, Cascade system, Vapor compression cycle