测量了制冷剂R22和R32/125（ASI 1990）（表现出共沸行为的50 wt%R32和50 wt%R125的混合物）的两相传热系数和压降特性。实验在制冷剂回路中没有油的情况下进行。冷凝器/蒸发器试验段由3/8英寸的光滑水平铜管组成。（9.53毫米）外径（外径）和0.305英寸。（7.75-mm）内径（ID）。冷凝器和蒸发器试验段的长度分别为10英尺（3.05米）和12英尺（3.5米）。 分别为66米）。冷凝器是一个逆流式热交换器，制冷剂在内管中流动，水-乙二醇混合物在环空中流动。蒸发器是一根光滑的铜管，中间夹着铝块。加热胶带缠绕在这些铝块的外表面上。平均饱和冷凝温度为115华氏度（46.1摄氏度）和125华氏度（51.7摄氏度），而饱和蒸发温度为40华氏度（4.4摄氏度）。冷凝试验的平均入口和出口质量分别为87%和25%，蒸发试验的平均入口和出口质量分别为20%和90%。 质量通量在118klb/ft2之间变化。h（160kg/s.m2）至414kb/ft2。h（561kg/s.m2）。差压传感器用于测量整个试验段的压降。结果表明，在相同的质量流量下，R32/125的冷凝换热系数略高于R22（约2%-6%）。R32/125的压降显著低于R22（约25%至45%）。然而，与R22相比，R32/125的蒸发传热系数要高得多（约23%至63%），其压降显著更低（约20%至38%）。 当系统设计为使用R32/125时，这将提高能效。关键词:1995年，制冷剂，R22，R32，R125混合物，热流，传热系数，压降，性能，共沸，测量，实验，更换，逆流热交换器，热交换器，比较引文:研讨会，ASHRAE Trans。1995年，第101卷，第一部分，论文编号CH-95-1-11525-527

The two-phase heat transfer coefficient and pressure drop characteristics of refrigerants R22, and R32/125 (ASI 1990)(a mixture of 50 wt% R32 and 50 wt% R125 that exhibits azeotropic behaviour) have been measured. The experiments were conducted without oil in the refrigerant loop. The condenser/evaporator test sections consist of smooth, horizontal copper tubes of 3/8-in. (9.53-mm) outer diameter (OD) and 0.305-in. (7.75-mm) inner diameter (ID). The lengths of the condenser and evaporator test sections are 10 ft (3.05 m) and 12 ft (3.66 m), respectively. The condenser is a counterflow heat exchanger with refrigerant flowing in the inner tube and a water-glycol mixture flowing in the annulus. The evaporator is a smooth copper tube sandwiched with aluminium blocks. Heating tapes are wrapped around the outer surface of these aluminium blocks. The average saturated condensing temperatures were 115degF (46.1degC) and 125degF (51.7degC), while the saturated evaporating temperature was 40degF (4.4degC). The average inlet and exit qualities for the condensation tests were 87% and 25%, respectively, and for the evaporation tests they were 20% and 90%, respectively. The mass flux was varied from 118klb/ft2.h (160kg/s.m2) to 414klb/ft2.h (561kg/s.m2). A differential pressure transducer was used to measure the pressure drop across the test section. The results showed that at similar mass fluxes the condensation heat transfer coefficients for R32/125 were slightly higher (about 2% to 6%) than those of R22. The pressure drop for R32/125 were significantly lower (about 25% to 45%) than those of R22. However, the evaporation heat transfer coefficients of R32/125 were much higher (about 23% to 63%), and its pressure drops were significantly lower (about 20% to 38%) than those of R22. This will lead to improved energy efficiency when systems are designed to utilise R32/125.KEYWORDS: year 1995, refrigerants, R22, R32, R125 mixtures, heat flow, heat transfer coefficient, pressure drop, properties, azeotropic, measuring, experiment, replacing, counter flow heat exchangers, heat exchangers, comparing