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摘 要： 实验研究了制冷剂/润滑油混合物在泡沫金属加热表面池沸腾的传热特性，分析了润滑油浓度和泡沫金属结构对池沸腾换热特性的影响。实验使用三种结构参数的泡沫金属作为加热表面，其参数分别为10PPI / 90%孔隙率、10PPI / 95%孔隙率、20PPI / 98%孔隙率，厚度均为5mm。实验使用的制冷剂为R113，润滑油为VG68，润滑油浓度为0-5%。实验结果表明：泡沫金属的存在极大提高了制冷剂/润滑油混合物的池沸腾换热系数，最多提高1.6倍；润滑油的存在会恶化制冷剂在泡沫金属加热表面池沸腾的换热，最多可降低15%的换热系数；相比平加热面，润滑油对泡沫金属加热表面池沸腾换热恶化的程度低。 关键字 ：泡沫金属 池沸腾 制冷剂 润滑油 关联式 Nucleate Pool Boiling Heat Transfer Characteristics Ofsaturated Refrigerant/Oil Mixtures Over Metal Foams Hu Haitao1 Zhu Yu1 Ding Guoliang1 Peng Hao1 Zhuang Dawei1 Yu Jun2 1Institute of Refrigeration and Cryogenics Engineering, Shanghai Jiaotong University, Shanghai 200240 China; 2Changsha Liyuan Novel Material Co., Ltd., Hunan Changsha 410100 China Abstract: The nucleate pool boiling heat transfer characteristics of refrigerant/oil mixture on metal foam covers are experimentally investigated. Three kinds of copper foams, with the geometry parameters of 10 ppi / 90% porosity, 10 ppi / 95% porosity and 20 ppi / 98% porosity are selected in this study. The refrigerant is R113 and the oil is VG68. The oil concentration is from 0 to 5%. The experimental results show that metal foam covers extremely enhance the pool boiling heat transfer of refrigerant/oil mixture, the heat transfer coefficient increases by up to 160% to that on plain surface; the presence of oil deteriorates the pool boiling heat transfer of refrigerant on metal foam covers, the heat transfer coefficient decreases by up to 15% to that of pure refrigerant; the deterioration of nucleate pool boiling heat transfer by oil on metal foam covers is lower than that on plain surface. Key words : Metal foam; Pool boiling; Refrigerant; Lubricant oil