非均匀产热圆盘辐射状和树状冷却流道构形设计

Constructal Design of Non-uniform Heat-generating Disc Inserted With Radialand Tree-shaped Cooling Channels

基于构形理论和理论,建立三维稳态非均匀产热圆盘“盘-点”对流传热模型以研究产热非均匀分布对电子器件热设计的影响。以耗散率与耗功率的复合函数最小为优化目标,得到不同产热分布条件下圆盘内部辐射状和树状冷却流道的最优构形,并采用NSGA-II算法对该多目标问题进行优化得到其Pareto最优解集。结果表明:1)在圆盘产热体内布置树状冷却流道可提升其对流传热综合性能;2)可将发热器件尽量安排在靠近冷却水入口处或者在散热需求大、热流密度高的区域布置冷却流道,以有效提升散热结构的冷却效果;3)基于线性加权法得到的最优解出现在采用NSGA-II算法优化后得到的Pareto前沿上,验证了数值结果的正确性,Pareto最优解集相比线性加权法更适用。

Based on constructal theory and entransy theory, a three-dimensional steady-state non-uniform heat-generating disc-shaped “disc-point” convective heat transfer model is built to research the influence of non-uniform heat generation on the thermal design of electronic devices. The minimum complex function composed of entransy dissipation rate(EDR) with the power consumption is utilized as optimization objective. Under different heat generation distributions, the optimal constructs of internal radial and tree-shaped cooling channels inserted in the disc-shaped volume are obtained. Furthermore, the NSGA-Ⅱ algorithm is introduced into the multi-objective optimization problem. By this means, the Pareto optimal solution sets are yielded. The results indicate that:1) deploying the tree-shaped cooling channels in the disc-shaped volume can elevate the overall convective performance;2) the heat-generating devices can be preferably arranged near the cooling channels as much as possible or arrange the cooling channels in the area with high heat dissipation demand and high heat flux, so as to effectively improve the cooling effect of the heat dissipation structure;3) the optimal solutions obtained from the linear weighted method appear on the Pareto frontiers by applying the NSGA-Ⅱ algorithm. Thus, the validity of numerical results is verified. The obtained Pareto optimal solution sets are more applicable than the counterparts yielded by the linear weighted method.