大功率半导体发光二极管液冷板散热性能分析

液冷板体积小，散热效果明显，被广泛应用于密集电子器件的散热。为研究液冷板内部的流动与传热过程，实现高效散热，利用计算流体力学(computational fluid dynamics, CFD)方法对液冷板进行热固耦合三维数值模拟，对比分析了水、乙二醇、酒精及甘油4种常见的不同类型冷却液在冷板内的流动规律与换热特性，研究了冷却液入口流速对综合散热性能的影响，并通过理论计算的方法加以验证。结果表明：设计的液冷板具有较好的流动和换热性能，4种冷却介质的综合散热效果均随入口流速增加而得到不同程度改善，最佳入口工况流速为2.5 m/s。以发光二极管芯片结温为散热性能指标，发现水的散热效果最佳，基板表面温度分布较为均匀。

Heat Dissipation Performance Analysis of High-Power LED Liquid-Cooled Cold Plate

Liquid-cooled cold plate is widely used in the heat dissipation of dense electronic devices because of its small volume and heat dissipation effect. In order to study the flow and heat transfer process in the cold plate and enhance the efficient of heat dissipation, a three-dimensional numerical simulation of liquid-cooled plate was carried out by using computational fluid dynamics (CFD). The flow and heat transfer characteristics of water, ethylene glycol, alcohol and glycerol were compared and analyzed, and the influence of different inlet velocity of 4 typical coolants on the overall heat dissipation performance was studied. A good agreement was found between numerical predictions and theoretical analysis. The results show that the liquid-cooled cold plate has a good performance in fluid flow and heat transfer, and the effect of heat dissipation of the coolants is improved with the increase of inlet velocity. The optimal inlet velocity of coolants is 2.5 m/s, taking LED chip junction temperature as the index of heat dissipation performance, the water offers the best heat dissipation with an uniform distribution of the substrate surface temperature. The results may provide a valuable reference for the optimization of cooling solutions and the improvement of efficiency of liquid-cooled cold plate.