基于计算流体力学热流固耦合仿真的换热器折流板结构优化

Structure Optimization for Heat Exchanger Baffle Based on Computational Fluid Dynamics Simulation of Thermal-Fluid-Structure Coupling

采用多物理场耦合方法,建立了管壳式换热器的计算流体力学(CFD)热流固耦合仿真分析模型,对20种不同折流板结构参数的管壳式换热器进行了流动与传热的数值模拟。CFD仿真计算结果显示,换热器的折流板间距和折流板缺口高度对流动和传热的影响相互关联,不能进行单目标优化设计。以JF因子作为换热器综合性能的评价准则,对管壳式换热器的折流板间距和折流板缺口高度进行了结构优化设计,提出在换热器内径(d)200 mm、换热管长1 140 mm、并流条件下,该换热器的最佳折流板间距为80 mm(折流板数目为10),最佳折流板缺口高度为0.3d(即60 mm)。

A thermal-fluid-structure coupling simulation model for shell-and-tube heat exchangers was established based on computational fluid dynamics（CFD） by a multi-physical field coupling method. The flow and heat transfer in 20 different types of shell-and-tube heat exchangers with different baffle structural parameters were simulated by the model. The CFD simulation results showed that the effects of the baffle spacing and baffle gap height on the flow and heat transfer interconnected, which showed that the single-objective optimization could not be achieved. With JF factors as the evaluation criteria of the heat exchanger performances, the baffle spacings and baffle gap heights in the shell- and-tube heat exchangers were optimized. It was put forward that under the conditions of parallel flow, inside diameter of the heat exchanger（d） 200 mm and heat exchange tube length 1 140 mm, the baffle space and baffle gap height were 80 mm（the baffle number 10） and 0.3d（60 mm）, respectively.