本文报道了R-134a和150 SUS季戊四醇酯支化酸润滑剂混合物在蒸发和冷凝过程中的平均传热系数和压降。本研究中测试的光滑管和微翅片管的外径为9.52 mm（3/8 in.）。微型翅片管有60个翅片，翅片高度为0.2毫米（0.008英寸），螺旋角为18°。本研究的目的是评估R-134a微翅片管的有效性，并确定循环润滑剂的效果。实验结果表明，与光滑管相比，微翅片管具有明显的性能优势。例如，微翅片管在蒸发和冷凝过程中的平均传热系数比光滑管高50%到200%，而平均压降平均仅高10%到50%。 实验结果表明，在高润滑剂浓度下，润滑剂的存在会降低蒸发和冷凝过程中的平均传热系数。蒸发过程中的压降随着两个管中添加润滑剂而增加。对于冷凝，添加润滑剂不会影响压降。单位:双引文:阿什雷交易，1998年，第104卷，第。1A，旧金山

This paper reports average heat transfer coefficients and pressure drops during the evaporation and condensation of mixtures of R-134a and a 150 SUS penta erythritol ester branched-acid lubricant. The smooth tube and micro-fin tube tested in this study had outer diameters of 9.52 mm (3/8 in.). The micro-fin tube had 60 fins, a fin height of 0.2 mm (0.008 in), and a spiral angle of 18°. The objective of this study is to evaluate the effectiveness of the micro-fin tube with R-134a and to determine the effect of circulating lubricant.The experimental results show that the micro-fin tube has distinct performance advantages over the smooth tube. For example, the average heat transfer coefficients during evaporation and condensation in the micro-fin tube were 50% to 200% higher than those for the smooth tube, while the average pressure drops were on average only 10% to 50% higher. The experimental results indicate that the presence of a lubricant degrades the average heat transfer coefficients during both evaporation and condensation at high lubricant concentrations. Pressure drops during evaporation increased with the addition of a lubricant in both tubes. For condensation, pressure drops were unaffected by the addition of a lubricant.Units: Dual