对纯R12和R134a管内冷凝的局部传热进行了实验和分析。数据取自57-18毫米a内径2.90米（9.5英尺）长的光滑铜管。试验段由两个逆流水回路冷却，每个回路覆盖试验段长度的一半。与试验段直径相同的观察镜位于试验段的进口和出口处，用于观察流态。数据是在以下范围内的测试条件下采集的:质量流量，75至500 kg/m2——s（55000至365000lbm/ft2——h），饱和温度，35摄氏度和60摄氏度（95华氏度和140华氏度），平均质量，10%至90%，热流量，4至15千瓦/平方米（1268至4756 Btu/h——ft2）。 当质量流量和质量较低时，观察到的流型呈波浪状，随着质量流量和质量的增加，流型依次通过波浪状环形、环形和雾状环形流型。波浪流动状态下纯制冷剂的数据与改进的Nusselt型方法成功关联，并且没有表现出质量流量依赖性。基于热传递和动量传递之间的类比，成功地关联了环形流数据。关键词:实验，计算，冷凝，制冷剂，R12，R134a，热流，管，铜，测试，饱和温度，流体流动，冷凝器，传热系数。 引用:研讨会，ASHRAE Trans。1994年，第100卷，第一部分

Experimental and analytical work has been performed on local heat transfer for in-tube condensation of pure R12 and R134a. The data were taken in a 4.57-mm (0.18-in.) ID smooth copper tube of 2.90 m (9.5 ft) length. The test section was cooled by two counterflow water circuits, each covering half of the test section length. Sight glasses of the same diameter as the test section were located at the inlet and outlet of the test section for visual flow regime observations. Data were taken with test conditions in the following ranges - mass flux, 75 to 500 kg/m2×s (55,000 to 365,000lbm/ft2×h), saturation temperature, 35 deg C and 60 deg C (95 deg F and 140 deg F), average quality, 10% to 90%, and heat flux, 4 to 15 kW/m2(1,268 to 4,756 Btu/h×ft2). The observed flow regimes were wavy at low mass flux and quality, progressing sequentially through the wavy-annular, annular, and mist-annular flow regimes as the mass flux and quality were increased. The data for pure refrigerants in the wavy flow regime were successfully correlated with a modified Nusselt-type approach and exhibited no mass flux dependence. The annular flow data were successfully correlated based on an analogy between heat and momentum transfer.KEYWORDS: experiment, calculating, condensation, refrigerants, R12, R134a, heat flow, tubes, copper, testing, saturation temperature, fluid flow, condensers, heat transfer coefficient.