本研究的目的是（a）在存在少量可混油的情况下，对氟里昂制冷剂R-12冷凝和蒸发过程中水平管流中的局部对流换热系数进行实验测量。（b） 在相同条件下进行压降的实验测量。（c） 建立预测传热和压力的关联式，并将这些关联式与实验数据进行比较。（d） 绘制流量图，预测油污染情况下的流型行为。 （e） 提高对双组分两相流行为的理解，特别是第二种非挥发性液体组分对冷凝或蒸发流体的影响。选择制冷剂R-12是因为它在油中完全可混溶。更常见的R-22只是部分混溶的，这将给已经很难解决的问题增加额外的复杂性。采用双管换热器结构，尽可能地模拟恒定壁温条件。环空中的液体是水。局部传热测量报告了广泛的流型。

The objectives of this study are(a) To perform experimental measurements of local convective heat transfer coefficient in horizontal tube flow during condensation and evaporation of Freon refrigerant R-12, in the presence of small amounts of a miscible oil.(b) To perform experimental measurements of pressure drop under the same conditions.(c) To develop correlations to predict heat transfer and pressure, and to compare these correlations to the experimental data.(d) To develop flow maps to predict the flow pattern behavior in the presence of oil contamination.(e) To improve understanding of the behavior of two-component two-phase flow, specifically the effect of a second non-volatile liquid component on a condensing or evaporating fluid.The refrigerant R-12 was selected because it is completely miscible in oil. The more common R-22 is only partially miscible and this would add an additional complication to an already difficult problem. Constant wall temperature condltions are simulated as nearly as possible by the double pipe heat exchanger configuration. The fluid in the annulus is water. Local measurements of heat transfer are reported over a wide range of flow patterns.