新型制冷剂R1234ze(E)(trans-1,3,3,3-tetrafluoropropene)因较低的GWP而被广泛关注,有望在热泵中作为R134a的替代品。本文对R1234ze(E)在内径为8 mm水平管内流动沸腾过程中摩擦压降特性进行实验研究,并在相同实验工况下与R134a进行对比。实验研究的流动沸腾换热的饱和温度为10℃,热流密度为5.0 kW/m2和10.0 kW/m2,质流密度范围为300~500 kg/(m2•s),并分析质流密度、热流密度对R1234ze(E)和R134a饱和流动沸腾过程中摩擦压降的影响。结果表明,在相同工况下R1234ze(E)的流动沸腾过程的摩擦压降略大于R134a,如质流密度为500 kg/(m2•s)时,R1234ze(E)的平均摩擦压降值比R134a大8.4％左右。最后,将实验结果同四种摩擦压降经验关联式进行比较分析。%Recently, more attention have been paid to the new refrigerant R1234ze(E), which is supposed to be the most promising al-ternative of R134a in heat pump system. In this paper, the saturated flow boiling frictional pressure drops characteristics of R1234ze(E) and R134a inside an 8 mm ID horizontal tube were investigated. The experiment were carried out at the saturation temperature of 10 ℃with heat flux ranging from 5. 0 kW/m2 to 10. 0 kW/m2 and mass flux ranging from 300 kg/(m2•s) to 500 kg/(m2•s). The influence of mass flux and heat flux on the frictional pressure drops were examined and discussed. The results show that, the frictional pressure drops of R1234ze(E) are slightly greater than those of R134a. Meanwhile, the experimental data of the frictional pressure drops are com-pared with four well-known empirical correlations.
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