超临界压力流体管内湍流对流传热的计算方法  

Computing method for convection heat transfer of supercritical pressure fluid in turbulent pipe flow

作　　者：毛宇飞[1] 曹飞[1] 上官燕琴 MAO Yufei;CAO Fei;SHANGGUAN Yanqin(College of Mechanical and Electrical Engineering,Hohai University,Changzhou 213200,Jiangsu,China)

机构地区：[1]河海大学机电工程学院,江苏常州213200

出　　处：《化工学报》2024年第8期2821-2830,共10页CIESC Journal

基　　金：国家自然科学基金项目(51506043,51206040);河海大学中央高校基本科研业务费项目(B230201020)。

摘　　要：将边界层积分方法应用于管内变物性湍流流动导出了剪切应力的分布方程,基于该方程可以对超临界压力流体的对流传热行为做出合理的定性解释。对于加热条件下的传热工况,结合“热可压缩”状态流体密度的变化,引入浮力阻力系数表征热流方向上的“浮力效应”,引入加速阻力系数表征流动方向上的“加速效应”。根据边界层理论和动量-热量传递比拟法导出了新型传热关联式,该关联式将不可压缩流体和热可压缩流体的管内湍流对流传热计算统一起来。应用关联式预测不同超临界流体的管内湍流对流传热系数,计算结果与实验数据的比较表明:关联式能较为准确合理地预测出大部分传热工况下的传热强化和传热恶化行为,其预测精度与摩擦阻力系数的计算有关。Boundary layer integration method is applied to variable property turbulent flow in tube,and the shear stress distribution equation is derived.Based on this equation,a reasonable qualitative explanation can be made for the convective heat transfer behavior of supercritical pressure fluid.For the heat-transfer cases under heating conditions,and a thermal resistance coefficient of buoyancy is proposed to indicate the buoyancy effect due to the fluid density variation in radial direction,a thermal resistance coefficient of acceleration is proposed to indicate the acceleration effect due to the fluid density variation in axial direction.According to the boundary layer theory and the analogy between momentum and heat transfer,a new correlation equation has been developed to unify the calculation of turbulent convection heat transfer in tubes for incompressible and thermally compressible fluids.The proposed correlation is applied to predict the turbulent convective heat transfer coefficients in tubes for different supercritical fluids.The comparison between the calculated results and the experimental data shows that the correlation formula can accurately and reasonably predict the enhanced heat transfer and deteriorated heat transfer behavior under most heat transfer conditions,and its prediction accuracy is related to the calculation of friction resistance coefficient.

关 键 词：超临界流体 湍流 对流 传热 热可压缩 关联式 

分 类 号：TK124[动力工程及工程热物理—工程热物理] O357.53[动力工程及工程热物理—热能工程]