新型管壳式换热器三维流场分析

Analysis of Fluid Flow Field in Shell Sides of Shell-and-Tube Heat Exchangers

本文应用周期性简化模型,对弓型、杆式以及H型壳程支撑结构的管壳式换热器壳程内的流动特性进行了分析。对于其对应的三种典型流态,反映在壳程内流体流动方面的主要差别是壳程内横向流速度分量的不同,且三种流态各自在不同流域下的横向流速度分量与纵向流速度分量之比几乎均为一定值。具有不同管束支撑结构的管壳式换热器壳程内流体阻力降与传热系数不同,主要原因在于其壳程内流体的横向流速度分量的大小仔在差别。

Analysis of fluid flow characteristics is carried out in shell sides of shell-and-tube heat exchangers with segmental baffle, rod baffle and H-shape baffle, by using periodic numerical models. The main distinction of the three typical flow types corresponding to these heat exchangers lies in different fluid transversal velocity component. The ratio magnitude of fluid transversal velocity component to longitudinal velocity component remains a constant for each flow type in different fluxes. The difference of pressure drop and heat transfer coefficient between shell-and-tube heat exchangers with varied baffles is caused mainly by different ratio magnitude of fluid transversal velocity component to longitudinal velocity component.