过渡流下三列圆柱传热特性的数值模拟

为了研究过渡流状态下管外流体流动与传热特性的影响因素,利用基于复合网格系统的计算方法,对不同横向间距比与纵向间距比下的三列交叉圆柱列进行数值研究。研究结果表明,纵向间距一定时,横向间距对旋涡的位置及强弱有显著影响,且因上游圆柱不稳定性尾流对下游圆柱的洗刷作用使圆柱列存在一个最佳横向间距使换热效果最佳;横向间距一定时,三列交叉圆柱列的换热效果均随纵向间距的增大而递减。

Numerical Simulation for Heat Transfer Characteristics of Three Offset Cylinder Arrays in Transition Flow

In order to study the effects of the flow and heat transfer characteristics of the outside tubes in transition flow , three offset cylinder arrays are conducted numerical simulation with the calculation method based on the compound grid sys-tem .The results show that ,when cylinder pitch in Ydirection ( Pt ) is particular ,cylinder pitch in X direction ( Ps ) has a significant influence on the location and strength of vortex and due to the instability tail flow of the upstream cylinder ,which has a washing effect on downstream cylinders ,an optimal Ps makes the heat transfer effect best ;when Ps is particular ,heat transfer effect of all the three column cylinders decreases with the increase of the Pt .