阵列式多孔微射流热沉结构优化及传热特性研究

Structure Optimization and Heat Transfer Characteristics of Multiple Holes Array Microjet Heat Sink

为解决陶瓷封装芯片温度过高导致失效问题,以一种矩阵式多孔微射流热沉为基础,构建了几种不同结构的热沉几何物理模型及传热和流动数学模型,并对其传热和流动特性进行了数值模拟研究。为了改善被冷却表面温度均匀性、提高热沉的冷却效果,对热沉的进、出气结构进行了优化,对比分析了分别加装圆柱、棱柱肋片时的传热效果。结果显示:相比于圆形回流的基础结构,侧面进气结构散热能力提升了2.7%;两层进气结构提升了5.4%,但两层进气结构会导致压损剧增;环形回流结构提升了8.6%。增加肋片结构可以大幅提高热沉换热效果,且棱柱肋片结构提升了15.3%,明显优于圆柱肋片结构的12.2%;适当增加肋片高度可以增强热沉换热能力。

In order to solve the problem of ceramic packaging chip failure caused by too high temperature,based on a multiple hole micro jet heat sink structure,several geometric physical models and heat transfer and flow mathematical models of heat sinks with different structures were constructed,while their heat transfer and flow characteristics were numerically simulated.In order to improve the temperature uniformity of the cooled surface and improve the heat transfer and cooling effect of the heat sink,the inlet and outlet structures of the heat sink were optimized,while the heat transfer effects were compared and analyzed when the cylindrical and prismatic fins were installed.The heat dissipation capacity of the side inlet structure is increased by 2.7%,as compared with that of the circular return structure.The two-layer intake structure increased by 5.4%,but the two-layer intake structure led to a sharp increase in pressure loss.The annular reflux structure is increased by 8.6%.Heat transfer efficiency of the heat sink can be greatly improved by including fin structure.The prismatic fin structure exhibited an increase of 15.3%,which is obviously higher than that(12.2%)of cylindrical fin structure.It is therefore concluded that heat transfer capacity of heat sink can be enhanced by increasing the fin height properly.