R507A/R134a复叠式空气源热泵热水系统性能分析

摘要

Based on the REFPROP software,the influence of the evaporating tempera-ture,condensing temperature and middle condensing temperature on the COP of R507A/R134a cascade air-source heat pump water heater system is calculated.An optimal middle condensing temperature and an optimal mass flow ratio between the low-temperature and high-temperature refrigerant are obtained.When the middle condensing temperature difference is 5 ℃,the evaporating temperature is -30 ℃,and the condensing temperatu-re is 80 ℃,the optimal middle condensng temperature is 27.5 ℃,the optimal COP is 2.447,and the optimal mass flow ratio is 0.6458.%基于REFPROP软件分析蒸发温度、冷凝温度、中间冷凝温度对R507A/R134a复叠式空气源热泵热水系统COP的影响,得出系统运行时的最佳中间冷凝温度以及低温级和高温级制冷剂的最佳质量流量比.在中间冷凝温差为5℃,蒸发温度为-30℃,冷凝温度为80℃时,最佳中间冷凝温度为27.5℃,系统的COP为2.447,低温级和高温级制冷剂的最佳质量流量比为0.6458.