本文以R134a为工质，在外径为16 mm的两种不同几何结构的水平三维微肋管内进行了沸腾换热实验，研究了质量流率、热流密度、蒸汽干度等因素对沸腾换热系数的影响。与相同工况下的水平光管比较，1#微肋管的换热强化因子在1.52.1之间,2#微肋管的换热强化因子在1.92.8之间。两种三维微肋管的比较结果显示，单位内表面积上具有更多的微肋数目的2#管的平均沸腾换热系数比1#管增加了2843%。
Experimental results of R134a boiling in two kinds of three dimensionalmicrofin tubes with 16mm outer diameter are presented. The effects of massflux, heat flux and vapor quality on the heat transfer coefficients arereported in this paper. Compared to the smooth tube, the heat transferenhancement ratio of 1# tube is between 1.5 and 2.1, and that of 2#tube is between 1.9 and 2.8. The heat transfer characteristics of the twokinds of tubes are also compared. We find that the average heat transfercoefficients of the 2# tube, which has a greater number of microfins persquare centimeter, are 28 43% higher than those of the 1# tube.
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