通过换热实验和CFD模拟,在Re=150~1,200范围内对布置有斜截式半椭圆柱型涡流发生器的矩形换热通道内的流动和换热特性进行研究,并对其强化换热机理进行了分析.结果表明,布置有涡流发生器的换热通道较光滑通道Nu增加,压降增大,并且强化效果随Re增大而增强.在涡流发生器布置处产生了纵向涡,使截面涡量值大幅增加,从而强化了换热过程.
The flow characteristics and heat transfer of the oblique-cut semi-elliptic cylinder shell in a rectangular channel with a Re range of 150—1,200 were investigated numerically and experimentally.The heat transfer augmentation mechanism was then analyzed based on the simulation results.The results show that,compared with smooth channel,Nu and pressure drop increase simultaneously in the channel with vortex generator,which has an increasingly positive effect on the heat transfer performance with the increase of Re. Moreover,it is found that the longitudinal vortex was generated around the vortex generator to increase the local vorticity,thus enhancing the heat transfer.