Field synergy equation for turbulent heat transfer and its application
Field synergy equation for turbulent heat transfer and its application
复制标题
DOI：
10.1016/j.ijheatmasstransfer.2007.10.001
复制
发表时间：
2007-12
影响因子：
5.2
通讯作者：
Qun Chen;Jianxun Ren;Ji’an Meng
中科院分区：
文献类型：
--
作者：
Qun Chen;Jianxun Ren;Ji’an Meng
基于极值能量耗散原理建立的具有一组指定约束的湍流传热场协同方程，可以用来增强整个流体流动域上时均速度场和时均温度梯度场之间的场协同作用，以优化湍流传热。场协同方程的解给出了对于给定的平均动能衰减量具有最佳场协同的最佳流场，其使传热最大化。作为算例，给出了平行平板间湍流换热的场协同分析。分析表明，在湍流流动中，边界附近存在小涡的速度场能有效地强化传热，特别是当垂直于主流方向的涡高度约为湍流过渡层厚度的一半时。在此最佳速度场的引导下，可以在平行平板上附加适当的内翅片，使其速度场接近最佳速度场，从而提高场协同效应，优化湍流换热。
A field synergy equation with a set of specified constraints for turbulent heat transfer developed based on the extremum entransy dissipation principle can be used to increase the field synergy between the time-averaged velocity and time-averaged temperature gradient fields over the entire fluid flow domain to optimize the heat transfer in turbulent flow. The solution of the field synergy equation gives the optimal flow field having the best field synergy for a given decrement of the mean kinetic energy, which maximizes the heat transfer. As an example, the field synergy analysis for turbulent heat transfer between parallel plates is presented. The analysis shows that a velocity field with small eddies near the boundary effectively enhances the heat transfer in turbulent flow especially when the eddy height which are perpendicular to the primary flow direction, are about half of the turbulent flow transition layer thickness. With the guide of this optimal velocity field, appropriate internal fins can be attached to the parallel plates to produce a velocity field close to the optimal one, so as to increase the field synergy and optimize the turbulent heat transfer.