在低翅片管内对冷冻油混合物的蒸发和冷凝进行了研究，并与光滑管和微翅片管试验的早期结果进行了比较。制冷剂为R-22，油为150 SUS环烷基矿物油。试验段是一根外径为0.375英寸（9.52毫米）、长度为12英尺（3.67米）的水平直管。试验段由周围环形空间中流动的水加热或冷却。油的质量浓度在0%到5%之间变化，质量通量在92000-294000 lb/hft2（125-400 kg/m2）之间变化。标称蒸发条件为37华氏度（3摄氏度），入口和出口质量分别为15%和85%。冷凝的标称条件为105华氏度（41摄氏度），入口和出口质量分别为85%和15%。 对于纯制冷剂，与光滑管相比，低翅片管的蒸发传热增强系数高达2.5，但随着油的添加，相对于光滑管的蒸发传热增强系数降低。使用纯制冷剂时，冷凝传热的增强系数高达2.2，并且相对于光滑管而言，随着油的添加，冷凝传热的增强趋势增加。尽管光滑管显示出少量油的蒸发传热增强，但低翅片管几乎没有显示出增强。低翅片管中的纯制冷剂蒸发性能与之前测试的微翅片管相当，但随着油的引入，低翅片管的相对性能降低。 在冷凝过程中，在测试的油浓度范围内，低翅片管的传热性能比微翅片管低约10%到15%。单位:双引文:研讨会，ASHRAE交易，1988年，第94卷，pt。2、渥太华

Evaporation and condensation of refrigerant-oil mixtures were studied inside a low-fin tube and compared with earlier results for smooth tube and micro-fin tube tests. The refrigerant was R-22 and the oil was a 150 SUS naphthenic mineral oil. The test section was a straight, horizontal tube with a 0.375 in (9.52 mm) outside diameter and a length of 12 ft (3.67 m). The test section was heated or cooled by water flowing in a surrounding annulus. The mass concentration of the oil was varied from 0% to 5%, and mass fluxes were varied from 92,000-294,000 lb/hft2(125-400 kg/m2•s). Nominal evaporation conditions were 37 F (3° C) with inlet and outlet qualities of 15% and 85%, respectively. Nominal conditions for condensation were 105 F (41° C) with inlet and outlet qualities of 85% and 15%, respectively.For pure refrigerant, the low-fin tube enhanced evaporative heat transfer by a factor as high as 2.5 compared to the smooth tube, but the enhancement relative to the smooth tube decreased as oil was added. Condensation heat transfer was enhanced by a factor as high as 2.2 with pure refrigerant, and the enhancement relative to the smooth tube tended to increase as oil was added. Although the smooth tube showed enhancement of evaporative heat transfer with small quantities of oil, the low-fin tube showed virtually no enhancement. The performance of pure refrigerant evaporation in the low-fin tube was equivalent to that in the previously tested micro-fin tube, but the relative performance of the lowfin tube decreased as oil was introduced. During condensation, the heat transfer performance of the lowfin tube was approximately 10% to 15% below that of the micro-fin tube over the range of oil concentrations tested.Units: Dual