入口位置及角度对微通道散热器内流体流动与传热的影响

Influence of inlet port position and angle on flow and heat transfer of microchannel heat sink

为进一步提升等截面微通道热沉的散热性能,本文设计了双进口-单出口型微通道热沉,并采用数值模拟的方法研究了入口上侧边布置、左侧边布置以及不同入口角度时去离子水在微通道热沉内的流动和传热特性。结果表明,进出口布置方式对微散热器内各通道流量分配有很大影响,而流量分配直接影响热沉的温度分布。入口上下侧边布置时流体的分布更加均匀,热沉的热阻和泵功较小。入口角度的减小降低了热沉底面温度,并使底面温度更加均匀。当Re=365时,θ=45°的底面最高温度比θ=90°时降低了1.91℃,但泵功却显著增大。

In order to further improve the heat dissipation performance of microchannel heat sink(MCHS)with equal cross-section,a two inlet ports-one outlet port MCHS was proposed in this paper.The flow and heat transfer characteristics in MCHS where the inlet ports were arranged at the upper side or the left side walls with different angles were analyzed by numerical simulation.The results showed that the layout of inlet and outlet ports had a great influence on flow distribution of each channel in the microchannel heat sink,and the temperature distribution was directly influenced by flow distribution.When the inlet ports are located at side walls of the heat sink,the fluid distribution was more uniform,and the thermal resistance and pump work of heat sink were smaller.The decrease of inlet ports angle reduced the bottom temperature of MCHS and made the bottom temperature more uniform.When Re was at 365,the maximum plate temperature atθ=45°was 1.91℃lower than that atθ=90°,but the pumping power increased significantly.