自然工质风冷太阳能双级喷射中低温空调制冷系统的设计及性能分析

依据中低温空调温度要求,分别以水、氨、R290和R600a为工质,设计了额定制冷量为10kW的风冷太阳能双级喷射制冷系统并对其进行变工况性能分析。在获得相同制冷量和室内温度的条件下,水系统最省材料,其次是氨和R290系统,且二者相当,R600a系统最耗材。4种工质系统均具有较强的变工况性能;综合考虑环境温度和太阳辐照度的影响,各系统制冷能力相当。水系统的COP较其他系统的高,且在低太阳辐照度时更明显;其余3个系统COP从高到低依次为氨、R290、R600a。在太阳辐照度较弱地区,使用水喷射制冷系统更合理。

Design and performance analysis of solar-powered air-cooled two-staged ejector cooling systems with natural refrigerants for middle and low temperature purpose

According to the requirement of middle and low temperature air conditioning,the solar-powered air-cooled two-staged ejector cooling system with rated cooling capacity of 10 kW is designed,using water,ammonia,R290 and R600a as working fluids separately.The performance is analyzed.At certain cooling capacity and indoor temperature,the water system is the most material-saving system,followed by the ammonia and R290 ones with equivalent consumption,and the R600a system is the most material-consuming one.The four systems have relatively perfect off-design performance and their cooling capacities are almost the same on comprehensive consideration of the influences of ambient temperature and solar irradiance.Among the four systems,the water system presents higher COP value,the effect of which is more obvious under weaker solar irradiance,followed by ammonia system,R290 and R600a systems. A solar-powered air-cooled ejector refrigeration system with water as working fluid is more suitable for use in the regions with relatively weak solar irradiance.