波浪形双层微通道热沉性能的传热优化分析

The optimization analysis of wavy double-layered microchannels heat sink by entransy dissipation

摘要:

本文基于CFD软件对波浪形双层微通道热沉的热性能进行三维数值研究,将传统的波浪形双层微通道热沉在面积不变的情况下对其入口截面形状进行改进,当入口流速u=1-2m/s,热通量在q=100000-600000W/m2范围内进行了一系列数值模拟,研究微通道热沉入口形状、流速以及热通量的对其温度、压降的影响。并基于（火积）耗散理论进行对比,得到波浪形双层微通道热沉传热的更优方案,在边界热流一定的条件下,（火积）耗散越小的微通道热沉换热效果更好。结果表明:随着微通道入口流速的增大,热沉温度逐渐降低,进出口压差逐渐增大,（火积）耗散逐渐减小。入口形状为上下层均为矩形时微通道热沉的温度比入口形状为上层五边形-下层矩形时微通道热沉的温度更高,PEC更大,（火积）耗散更小,传热效率更高。

Abstract:

:Based on the CFD software of the wavy microchannel radiator thermal performance of the three dimensional numerical study, the traditional wavy double microchannel heat sink channel entry under the condition of invariable in the area of the cross section shape was improved, the inlet velocity is 1-2 m/s, A series of numerical simulations were carried out in the heat flux range of 100000-600000kw/m2 to study the influence of different micro-channel inlet shapes, inlet velocity and heat flux on heat sink temperature and pressure drop.Based on the comparison analysis of the entransy dissipation theory, a more optimal solution for heat transfer in wavy double-layer microchannels is obtained. The better the heat transfer effect of microchannels under specific boundary heat flow circumstances, the lesser the energy dissipation. The findings demonstrate that as the microchannel"s inlet flow rate rises, the heat sink temperature gradually falls, the pressure differential between the inlet and exit rises, and the energy dissipation gradually falls. Compared to the upper Pentagon lower rectangular inlet shape, the temperature of the microchannel heat sink is higher with the upper and lower rectangular inlet shape. The heat transmission efficiency is higher, the PEC is larger, and the energy dissipation is less.