管内填充环状金属多孔介质强化传热优化分析

Optimization Analysis of Heat Transfer Enhancement in Tube by Filling with Annular Metallic Porous Medium

在圆管内层流充分发展段填充环形金属多孔介质以实现强化传热,建立了流动与传热的数学模型,并着重分析了多孔介质填充位置对管内速度、温度分布以及传热综合性能的影响。数值模拟结果表明:填充金属多孔介质的区域温度非常均匀,速度分布趋于平坦,而未填充多孔介质的区域速度及温度梯度均较大,壁面与流体之间的换热显著增强;此外,对于填充一定截面积多孔介质的圆管,为获得较高的PEC值,宜将多孔介质的填充位置靠近圆管中心。

In order to enhance heat transfer rate of tube flow,the inner part of fully-developed laminar tube flow is filled with annular metallic porous medium,and mathematical models to describe its flow and heat transfer characteristic are established in this paper,which emphasize the different temperature,velocity and PEC results of enhanced tube with different positions of metallic porous medium.Numerical simulation results show that the temperature and velocity of the zone filled with metallic porous medium are very uniform,while the temperature and velocity gradient are very large in the flow without metallic porous medium,which shows that heat transfer between the wall and the flow is enhanced greatly.In addition,it is appropriate,for a certain constant filling area,to fill the core flow with metallic porous medium in order to achieve a comparatively higher PEC value of the enhanced tube.