小通道内的冷凝换热模型分析.pdf

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第48卷第24期
机槭工程学报
Vol48 No 24
2012年12月
JOURNAL OF MECHANICAL ENGINEERING
Dec
2012
DOI:10.3901/JMIE.2012.24.134
小通道内的冷凝换热模型分析
胡灿李敏霞马一太付兴
(天津大学中低温热能高效利用教育部重点实验室天津30002)
摘要:目前国内外对于大通道内的冷凝换热研究较多,而对小通道内的冷凝换热研究较少,小通道内重力、切应力、表面张
力的相互作用与大通道不同,导致小通道内的冷凝换热机理不同于大通道,因此大通道内的冷凝换热模型不能很好地预测小
通道内的冷凝换热,而小通道内冷凝换热的研究对设计和优化紧凑型换热器具有重要意义。总结9种小通道内的冷凝换热预
测模型,并根据11个独立研究机构的测试结果,收集6种工质(R134a,R32,R22,R123,R410A,R1234yf的1183个小通
道内的冷凝换热试验数据点。比较各模型的预测结果和数据点发现,各预测模型并不是适用于小通道内所有工质和工况的预
测,应根据工质和工况选择合适的模型。 GARIMELLA的预测模型対R134a、R32、R2入、R1234yf的数据点的预测误差很小
而 KOYAMA的预测模型适用范围比较广,大部分工况下误差也是可接受的
关键词:小通道冷凝换热预测模型
中图分类号:TB61
Analysis of Condensation Heat Transfer Model in Small Channels
HU Can LI Minxia MA Yitai FU Xing
(Key Laboratory of Medium-low Temperature Energy Efficient Utilization of Ministry of Education,
Tianjin University, Tianjin 300072)
Abstract: There are many researches about condensation heat transfer in macro-channels, but the studies of condensation heat
transfer in small channels is limited available, and the interaction of gravity, shear stress and surface tension in small channels is
different with macro-channels result that the mechanism of condensation heat transfer in small channels is different with
macro-channels, therefore condensation heat transfer prediction model of macro-channels can not predict heat transfer coefficients of
small channels very well. While, the research of condensation heat transfer in small channels is significance for designing and
optimizing compact heat exchanger. Nine condensation heat transfer prediction models of small channels are addressed, and a
database is setup by collecting I 183 condensation heat transfer data points of small channels which involves six types of
refrigerants(R 134a, R32, R22, R123, R410A, R1234yf )from 11 independent research groups. On basis of the comparison between
the prediction results and the database, t is found that most of prediction models cannot capture the points of all fluids under various
operating conditions in small channels, proper model should be chosen according to refrigerants and operating conditions
Garimella's prediction model is the best one for R134a, R32, R22and R1234yf. Koyama's model can almost fit for all data under
most of the operating conditions within an acceptable deviation
Key words: Small channels Condensation heat transfer Prediction model
域中使用。通过采用小通道来改善系统的结构可以
0前言
减少危险工质的存储量并减少温室气体排放量。在
空冷式冷凝器中,小通道的紧凑性降低了空气侧的
为了获得高换热效率的紧凑型换热器,小通道压降、提高了系统的换热效率,从而改善了系统的
的概念被广泛使用。目前小通道内的冷凝换热主要能效。小通道的使用还促使制冷剂的充灌量减少,
在电子设备的热管、紧湊型换热器及冷冻冷藏等领这就有利于有毒或易燃制冷剂的使用。此外,小通
道能承受较高的压力,因此能较好地用于高压工质,
“国家目然科学基金资助项目(S11300收到初稿,2012109例如用于二氧化碳跨临界循环设备中叫。日前还没