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研究了Ｒ１３４ａ、Ｒ１４２ｂ在光滑管和机械加工表面多孔管水平管外的池沸腾换热性能，分析了工质在水平管外的沸腾传热机理，实验的对比压力Ｐ／Ｐｃ＝０．２０。实验结果表明，光滑管外沸腾实验结果与取平均表面粗糙度为２μｍ的Ｇｏｒｅｎｆｌｏ公式预测结果吻合较好，与光滑管相比，机械加工表面多孔管能显著地强化沸腾传热，且随着热流密度的增加，强化倍率减小。通过数据拟合，得到了沸腾换热系数的经验关系式。
The pool boiling heat transfer performance of R134a and R142b outside the horizontal tubes of smooth tubes and machined porous tubes was studied. The mechanism of boiling heat transfer outside the horizontal tubes was analyzed. The experimental pressure P / Pc was 0.20. The experimental results show that the results of the smooth tube boiling experiment are in good agreement with the predicted results of the Gorenflo formula with an average surface roughness of 2 μm. Compared with the smooth tube, the machined porous tube can significantly enhance the boiling heat transfer, Increasing the density reduces the enhancement ratio. Through data fitting, the empirical relationship of boiling heat transfer coefficient was obtained.