大型中心型换热器内流量分配特性数值分析

Numerical analysis of flow distribution characteristics in large central-type heat exchangers

为了解非能动安全壳热量导出系统大型中心型集管式换热器内部流量分配特性,并为其后续设计提供相应参考依据。本文对大型中心型集管式换热器内部流量分配特性开展了数值计算研究。结果表明:增大传热管内流动阻力、增大联箱直径、弧形三通的应用、采用等径分配联箱与汇流联箱等方式,均有利于换热器内流量的均匀分配。而中心管间距过小则会对流量分配带来明显不利影响。传热管管束顺排或叉排布置方式对流量分配不均匀性及换热器内流动阻力基本无影响。

This paper presents a numerical study on flow distribution characteristics in large central-type compact parallel flow heat exchangers by the CFD method to understand the flow distribution characteristics of the heat exchangers of the passive containment heat removal system and provide a corresponding reference for its subsequent design.Results reveal that increasing the flow resistance in the heat transfer tube,increasing the header diameter,the use of curved tee and adopting equal diameter for the distribution header and the combined header are all beneficial to the uniform flow distribution for central-type compact parallel flow heat exchangers.Results reveal that increasing the header diameter and the flow resistance in the heat transfer tube using curved tees and adopting equal diameters for the distribution and combined headers are all beneficial to the uniform flow distribution for central-type compact parallel flow heat exchangers.