微肋管内的换热强化的实验和理论分析  

Experimental and theoretical analysis of heat transfer enhancement inside micro-fin tube

作　　者：申道明 桂超[1] 刘亚萍 夏锦红 薛松涛 Shen Daoming;Gui Chao;Liu Yaping;Xia Jinhong;Xue Songtao(College of Civil Engineering and Architecture,Xinxiang University,Xinxiang 453000,China;Research institute of structural engineering and disaster reduction,Tongji university,Shanghai 200092,China;Department of Architecture,Tohoku Institute of Technology,Sendai 9828577,Japan)

机构地区：[1]新乡学院土木工程与建筑学院,新乡453000 [2]同济大学结构工程与防灾研究所,上海200092 [3]日本东北工业大学,日本仙台9828577

出　　处：《低温工程》2019年第3期1-7,共7页Cryogenics

基　　金：国家自然科学基金项目(No.4187725)

摘　　要：在1根光管、2根微肋管内运行了R1234yf两相流动冷凝换热实验,工况设定中冷凝温度为40℃、43℃、45℃,质量流量为500-900 kg/(m^2·s),换热管进出口处制冷剂干度分别为0.8-0.9、0.2-0.3。实验结果显示:传热系数随冷凝温度的降低、质量流量的增加而增大,且微肋管内传热系数均大于光管内传热系数,其中8°和15°肋片螺旋角微肋管换热强化倍率分别为2.51-2.89、3.11-3.57,均大于其面积增加比;使用关联式对管内传热系数预测时:Cavallini et al关联式对光管内传热系数预测精度最高,其预测误差范围在±8%以内,预测平均误差为0.56%;Cavallini et al关联式和Koyama et al关联式对微肋管内传热系数预测精度较高,其预测误差范围在±25%以内,两者的平均预测误差小于6%。The two-phase flow condensation heat transfer experiment of R1234 yf was performed inside one smooth tube and two micro-fin tubes in the paper, experimental condition was set as condensation temperatures of 40 ℃, 43 ℃ and 45 ℃, mass fluxes of 500-900 kg/(m^2·s), vapor qualities at the inlet and outlet of heat transfer tube of 0.8-0.9 and 0.2-0.3. Experimental results show: the heat transfer coefficient increases with decreasing condensation temperature and increasing mass flux, the heat transfer coefficient inside the micro-fin tube is larger than that of smooth tube, the heat transfer enhancement factor of micro-fin tube with fin helical angle of 8° and 15° is 2.51-2.89 and 3.11-3.57, respectively, which are greater than the area increase ratio. Correlation was used to predict the heat transfer coefficient inside the tube and it is found: Cavallini et al correlation has the highest accuracy in predicting the heat transfer coefficient inside the smooth tube with error range within ±8% and average prediction error of 0.56%;correlations of Cavallini et al and Koyama et al have relatively high in predicting the heat transfer coefficient inside the micro-fin tube with error range within ±25% and average prediction error of less than 6%.

关 键 词：R1234yf 微肋管 传热系数 换热强化倍率 关联式 

分 类 号：TB66[一般工业技术—制冷工程] TB61