相溶性对R32-润滑油混合物管内流动沸腾换热及压降特性的影响  

Effect of Intermiscibility on Internal Flow Boiling Heat Transfer and Pressure Drop Characteristics of R32-oil Mixture

作　　者：李广 庄大伟[1] 谢丽懿 丁国良[1] 胡国新[1] 郑立宇 廖四清 卢耀汕 阚望 龙春仙 Li Guang;Zhuang Dawei;Xie Liyi;Ding Guoliang;Hu Guoxin;Zheng Liyu;Liao Siqing;Lu Yaoshan;Kan Wang;Long Chunxian(School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai,200240,China;Guangdong Meizhi Compressor Limited,Foshan,528300,China)

机构地区：[1]上海交通大学机械与动力工程学院,上海200240 [2]广东美芝制冷设备有限公司,佛山528300

出　　处：《制冷学报》2023年第5期70-77,87,共9页Journal of Refrigeration

摘　　要：R32已成为家用空调器的主流制冷剂,其换热性能受到溶入其中的润滑油相溶性影响,为此需要确定有利于提升换热性能的最佳相溶性。本文通过实验测试R32与完全互溶、部分互溶和完全不互溶的润滑油形成的混合物在换热管内的流动沸腾传热系数与压降,研究了相溶性导致的R32-润滑油分层现象及其对于换热与压降的影响机制。为覆盖空调器实际运行工况并体现R32与润滑油的不同相溶性,实验工况选取蒸发温度为-5~15℃,平均干度为0.2~0.7,平均油浓度(质量分数)为1%与5%。实验结果表明:三种油品中部分互溶润滑油的传热系数最高,压降最低;当蒸发温度为5℃、干度为0.7、平均油浓度为5%时,部分互溶润滑油相比于完全互溶与完全不互溶润滑油的优势达到最大,传热系数最大提升幅度分别达36.8%和357.8%,压降最大降幅分别达9.0%和58.2%。在三种油品中,部分互溶润滑油表现出最好的换热及压降特性,具有更好的应用前景。R32 is widely used in room air-conditioners,with heat transfer characteristics affected by the intermiscibility of the oil.Therefore,it is necessary to determine the optimal intermiscibility of the oil to improve heat transfer characteristics.This study investigated the influence of stratification,caused by the intermiscibility of the R32-oil mixture,on the heat transfer characteristics.The flow boiling coefficient of heat transfer and pressure drop of a completely miscible R32-oil mixture,a partially miscible R32-oil mixture,and a completely immiscible R32-oil mixture were tested experimentally.To cover the working conditions of air conditioners and reflect the different intermiscibilities of the R32-oil mixtures,the test conditions included evaporating temperatures from-5 ℃ to 15 ℃,vapor quality from 0.2 to 0.7,and averaged oil concentrations(mass fraction) of 1% and 5%.The results showed that partially miscible oil had the highest coefficient of heat transfer and the lowest pressure drop;at an evaporating temperature of 5 ℃,vapor quality of 0.7,and averaged oil concentration of 5%,the advantage of a partially miscible R32-oil mixture over that of the completely miscible and completely immiscible mixtures increased.The maximum increases in heat transfer coefficient were 36.8% and 357.8%,and the maximum decreases in pressure drop were 9.0% and 58.2%,respectively.Among the three types of oils,the partially miscible oil exhibited the best heat transfer and pressure drop characteristics and thus has the best application prospects.

关 键 词：R32 润滑油 相溶性 流动沸腾 传热系数 

分 类 号：TB611[一般工业技术—制冷工程] TK124[动力工程及工程热物理—工程热物理]