椭圆形丁胞数目及分布对传热管内流动和传热特性的影响

通过建立含不同参数椭圆形丁胞的传热管有限元模型,仿真研究雷诺数Re在5000~40000范围内椭圆形丁胞数目、轴向间距及交叉分布对传热管内流体介质流动及传热特性的影响规律。仿真研究结果表明,相比于光滑传热管,椭圆形丁胞的存在将增强对流传热的效果,且雷诺数Re越大越明显,但同时也会增加流体通过传热管时的流动阻力。此外,在雷诺数Re=40000时,椭圆形丁胞圆周分布数目N=6、轴向间距P=14 mm以及交叉分布角度为0°对传热管内流体的流动和传热综合特性影响最大,相比于光滑传热管,PEC分别达到1.156,1.15和1.13。

Influence of Number of Elliptical Dimples and Their Distribution on Flow and Heat Transfer Performance of Tube

The numerical simulation model of an ellipsoidal dimple tube with different parameters was established considering thermal-hydraulic performance.The effect of number,axial spacing and cross distribution of dimples on the flow field characteristics and heat transfer characteristics of an ellipsoidal dimple tube were discussed under Reynolds numbers between 5000 and 40000.The numerical results show that compared with the smooth tube,the presence of ellipsoidal dimples on the surface of tube will enhance the convective heat transfer effect,and the larger the Reynolds number is,the more obvious it is,but it will increase flow resistance of the fluid through heat transfer tube.In addition,when Reynolds number Re=40000,the circular distribution number N=6,axial spacing P=14 mm and cross distribution angle is 0°,the influence on thermal-hydraulic performance was the largest,compared with smooth tube,PEC reached 1.156,1.15 and 1.13,respectively.