雨滴型凹坑流道换热板流动换热性能与优化

Optimization and Heat Transfer Performance of Plate heat exchanger with Rain-drop Dimples

中文关键词: 雨滴型凹坑  板式换热器  强化传热  多目标优化  数值分析

英文关键词: Rain-drop dimple  Plate heat exchanger  Enhanced heat transfer  Multi-objective optimize  Numerical analysis

中文摘要:

      基于workbench,研究了雨滴型凹坑流道换热板的流动换热性能,并对其进行多目标优化研究。以努塞尔数Nu,阻力系数f,综合传热性能pec为目标函数,考察了凹坑的前缘半径R₁,后缘半径R₂,凹坑深度H_d,凹坑间距P等结构参数对雨滴型凹坑流道各优化目标的影响。结果表明：雨滴型凹坑流道内的流动分离和涡流碰撞增强了湍流强度,有效强化了传热,并且高传热区出现在凹坑后缘。雨滴型凹坑板的Nu值是平板的1.9~4.5倍,阻力系数是平板的2.3~3.5倍, pec值可达1.42~3.04。凹坑深度H_d对Nu,f,pec影响都比较显著,而凹坑间距P对这三者的影响都比较小,当3.5mmd<4.5mm且25mm1<30mm时有较好的pec。通过对雨滴型凹坑板在1358≤Re≤6926的数据结果进行关联,得到了凹坑板流动换热的准则关系式。

英文摘要:

      The heat transfer performance of plate heat exchanger with rain-drop dimple was studied and optimized based on the Workbench software, and the influence of R1, R2, Hd, P on heat transfer performance are investigated with Nu, f, pec serving as the objective function．Results show that the flow separation and vortex impingement appearing in the channel with rain-drop dimple enhances the turbulence intensity and improves heat transfer, and higher heat transfer area of the dimple appears at the trailing edge of the dimple structure. The Nu of rain-drop dimpled plate can be 1.9~4.5 times than that of the smooth plate, correspondingly, frictional loss factor is 2.3~3.5 times than that of the smooth plate, so the overall heat transfer performance evaluation criterion (pec) value can reach up to 1.42~3.04. Hd has the most obvious effect on Nu, f, pec, while the P has the weakest effect. pec has an optimal value when the 3.5mm