低温热泵系统中R290替代R22的性能研究及优化
Performance Study and Optimization on Alternative Refrigerant R290 in R22 Low Temperature Heat Pump System

本文从实验角度研究了R22低温热泵系统中R290的替代性能，通过对比不同工况下两者的性能差异发现：直接在原系统中将R22抽出灌装R290时，系统换热量与COP均有所衰减，且在低温环境中R290系统的压缩机排气温度和排气压力均高于原R22系统。通过分析系统部件可知，上述现象出现的主要原因是R22系统压缩机排量过大、与R290系统不匹配，因此为同时满足系统的安全性要求以及提高R290在低温热泵系统中的整体性能，考虑在系统中更换与R290更为匹配的排量更小的压缩机。实验结果表明：对R290低温热泵系统压缩机排量进行优化能有效降低系统的排气温度和压力、提高系统整体性能；压缩机优化后的R290低温热泵系统COP较原R22系统提高6.5%，低温环境下排气温度降低36%，至80 ℃以下。
This study addresses the experimental performance of the alternative refrigerant R290 in the R22 low-temperature heat pump system. Results show that when R22 was directly replaced by R290 in the original system, both the heat exchange and coefficient of performance (COP) of the system decreased, and the exhaust temperature and pressure of the R290 system were higher than those of the original R22 system at low temperatures. Through the analysis of the system components, reducing the displacement of the compressor of the R290 heat pump system can effectively improve overall performance and reduce the discharge temperature and pressure. After the optimization of the compressor, the R290 system achieved a 6.5% higher COP compared to the original R22 system, and the exhaust temperature was decreased to 80 °C, which is 36% lower than the R22 system