中高温热泵混合工质的循环性能分析

Analysis on performance of refrigerant mixture for moderate and high temperature heat pump

针对传统制冷剂R22和R134a在中高温领域的使用限制,探究以R22,R134a为核心的非共沸混合工质在热泵系统中的应用,通过建立混合工质在系统循环中的热力学模型对初步筛选的六种高温工质进行系统循环模拟分析,探讨热泵系统在设定工况下最适宜的混合工质及其配比,结果表明:冷凝区间60~80℃内,R22+R124和R134a+R142b相比其他组合有较好的循环性能,在冷凝温度为75℃,蒸发温度分别为20℃、7℃、0℃三种工况下,R22+R124的最适宜配比为0.65/0.35、0.4/0.6和0.3/0.7,R134a+R142b的最适宜配比为0.8/0.2,并且与R22+R142b进行比较,在对应工况下,R22+R124的单位容积制热量是R22+R142b的1.33、1.26和1.24倍。

In order to solve the limitation of the use of traditional refrigerants R22 and R134 a in the moderate and high temperature fields, the application of non azeotropic mixtures with R22 and R134 a as the core in heat pump system was explored.Based on the thermodynamic model of mixed working fluid in the system cycle, the simulation analysis of six kinds of high-temperature working fluids preliminarily selected was carried out, and the optimal mixture and its ratio of heat pump system under the different conditions were discussed.The results show that R22+R124 and R134 a+R142 b have better cycle performance than other combinations in the condensation range of 60~80 ℃.When the condensation temperature is 75 ℃, the evaporation temperature is 20 ℃, 7 ℃, and 0 ℃,the optimal ratio of R22+R124 is 0.65/0.35, 0.4/0.6 and 0.3/0.7, and the optimal ratio of R134 a+R142 b is 0.8/0.2.Compared with R22+R142 b, the unit volume heating capacity of R22+R124 is 1.33, 1.26 and 1.24 times of R22+R142 b under three correspongding conditions.