不同结构形式微通道热沉的传热性能

Heat transfer performance of microchannel heat sinks with different structures

为有效提高微通道热沉的散热性能,设计一种微针肋交错排布微通道热沉,即微针肋垂直于底面或通道侧面的微通道,旨在适当牺牲部分压降的同时提高热沉的换热性能,并与传统矩形微通道热沉做对比。采用数值模拟方法,对不同微通道流动特性、传热特性和熵产特性进行分析。结果表明:与其他几种微通道相比,当采用相邻微针肋间距为1 mm的交错排布微通道SC2时,在牺牲一定压降的同时传热性能得到提高,改善微通道底面温度分布均匀性。相较于传统矩形微通道,在入口雷诺数为716时,其底面最高温度下降25.84 K,热阻下降约55.1%,努塞尔数增大158%左右,整体传热性能CPE达1.69。

In order to effectively improve the heat dissipation performance of the microchannel heat sink,a microchannel heat sink with staggered arrangement of micro pin fins was designed,which was a microchannel with micro pin fins perpendicular to the bottom surface or the side of the channel.The aim was to improve the heat transfer performance of the heat sink while sacrificing part of the pressure drop appropriately,and comparing with the conventional rectangular microchannel heat sink.The flow characteristics,heat transfer characteristics and entropy production characteristics of different microchannels were analyzed by numerical simulation.The results show that comparing with other kinds of microchannel,when the staggered microchannel SC2 with adjacent micro pin fins spacing of 1 mm is used the heat transfer performance is improved at the expense of a certain pressure drop,and the microchannel bottom temperature distribution uniformity is improved.Compared with the traditional rectangular microchannel,when the inlet Reynolds number is 716,the underside highest temperature drops 25.84 K,thermal resistance fells about 55.1%,the Nusselt number increases by about 158%,and the overall heat transfer performance C PE reaches 1.69.