【摘要】 采用三维数值模拟获得错流式微型换热器温度分布、总包传热系数和传热单元数,给出了总包传热系数关联式,通过一维对流-导热耦合模型给出纵向导热影响系数K.K为流体质量流量、流体比定压热容、流体和间壁固体热导率及换热器结构尺寸的函数.用K和关联式求得的总包换热系数相乘的方法预测错流式微型多通道换热器的总包换热系数,与模拟结果吻合较好.更多还原

【Abstract】 Three-dimensional numerical simulation was used to obtain temperature distribution,overall heat transfer coefficient and heat transfer unit number of a cross flow mini-heat exchanger.The heat transfer coefficient correlation was given from the simulation.A one-dimensional convection-conduction coupled model was employed to develop a coefficient of longitudinal conduction effect K,which was a function of fluid mass flow rate,specific heat capacity of fluid,thermal conductivity for fluid and wall material and the structural parameters of the heat exchanger.The coefficient K was used to correct the overall heat transfer coefficient of the cross flow mini-heat exchanger.A calculating method for the heat transfer coefficient was that the coefficient K was multiplied by the overall heat transfer coefficient which was calculated from the heat transfer coefficient correlation.The estimated overall heat exchange coefficient by the proposed method was compared with simulated results and satisfactory agreement was obtained.更多还原