R245fa高温节流特性的试验研究

Experimental investigation on R245fa throttling under high temperature

为获得以R245fa为工质的高温热泵系统节流装置的设计选型依据,本文对R245fa的节流装置在高温工况下的流量进行了试验研究,主要对7根毛细管样件和一款电子膨胀阀产品在不同的高温运行工况下进行了流量测试,通过测试数据分析并结合流量关联式得出适用于R245fa的毛细管和电子膨胀阀在高温工况下的设计依据,结果表明,采用Jung关联式预测毛细管流量的均方根偏差为3.2%,采用Kim模型的均方根偏差为3.3%,电子膨胀阀流量系数的均方根偏差是4.5%。该结论为R245fa高温热泵系统毛细管和电子膨胀阀的选型提供了设计选型依据。

The experiments on mass flow rate characteristics of R245 fa refrigerant flowing through throttling devices including seven capillary tubes and the electronic expansion valve were carried out under the high-temperature working conditions.By combining regression analysis with flow correlations,the design basis that is applicable to R245 fa throttling devices can be obtained.By comparing the experimental data with predicted data by Jung Correlation and Kim Correlation,it can be concluded that root mean square deviations of two correlations are 3.2%and 3.3%,respectively.The root mean square deviation for electronic expansion valve is 4.5%.The conclusions offer high-accuracy design basis for throttling devices selection of high-temperature heat pump systems using R245 fa as refrigerant.