基于热阻分析的管道层流换热机理及强化换热作用研究  

Research on the mechanism of laminar heat transfer in pipes and enhanced heat transfer effect based on thermal resistance analysis

作　　者：张玮瑛 陈力勤 贾玉文[1] ZHANG Weiying;CHEN Liqin;JIA Yuwen(China Institute of Automatic Energy,Department of Nuclear Engineering Design,Beijing 102413,China;China Institute of Automatic Energy,Reactor Engineering Technology Research Institute,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院核工程设计研究所,北京102413 [2]中国原子能科学研究院反应堆工程技术研究所,北京102413

出　　处：《热力发电》2023年第7期119-125,共7页Thermal Power Generation

摘　　要：传热传质过程的分析对传热传质工作设备的性能改善有重要的指导意义。通过对边界层内热阻的分析,探索管道层流内部对流热阻与导热热阻在边界层内的发展,建立了符合宏观表征的机理模型(R-P模型)。使用该模型分析了在不同雷诺数Re和普朗特数Pr条件下的热阻分布规律,探究了管内层流强化换热的内在机理,并指导扰流结构的优化设计。结果表明,入口段导热作用占主导,完全发展后对流作用占比逐渐增大。Re和Pr影响换热的机理不同:Re增大,换热一定加强;Pr增大,只是增大了对流作用的占比,且在Pr小于1.8范围内,导热热阻始终占主要作用。同时发现,在管道层流添加扰流结构反而会降低换热效果。The analysis of heat and mass transfer process has important guiding significance for the performance improvement of heat and mass transfer equipment.Through the analysis of the thermal resistance in the boundary layer,the author explores the development of the convective thermal resistance and thermal conduction thermal resistance in the laminar flow of the pipeline in the boundary layer,and establishes a mechanism model(R-P model)that conforms to the macroscopic characterization.The thermal resistance distribution law under the condition of Re and Pr,explored the internal mechanism of laminar flow enhanced heat transfer in the tube,and guided the optimal design of the flow-around structure.The results show that the heat conduction is absolutely dominant in the inlet stage,and the proportion of convection gradually increases after the full development.The mechanism of Re and Pr affecting heat transfer is different.When Re increases,the heat transfer must be strengthened.When Pr increases,it only increases the proportion of convection,and in the range of(Pr<1.8),thermal resistance always plays a major role.At the same time,it was found that adding a turbulent flow structure to the laminar flow in the pipeline would reduce the heat transfer effect.

关 键 词：对流换热机理 热阻分析模型 热阻分布规律 强化对流换热优化 

分 类 号：TL333[核科学技术—核技术及应用]