液冷式CPU散热器的传热强化及流阻性能

Research on Heat Transfer and Flow Performance of Liquid Cooling Heat Sink for CPU

通过在液冷式CPU散热器蛇形流道内填充不同粒径的不锈钢珠,使液冷式CPU散热器流道形成类似＂多孔介质＂的复杂流道以提高其散热性能。通过对改进前后液冷式CPU散热器的试验研究,分析了各因素对液冷式CPU散热器的传热和流阻性能的影响规律。结果表明：在本试验范围内,相同Re和Pr下,改进后散热器的对流换热系数为改进前的1.2~4.8倍,阻力系数f是改进前的1.4~4倍;散热器填充Φ4mm开孔不锈钢珠的强化传热效果最佳,芯片表面温度较填充前降低了33,°对流换热系数增大4.8倍,而流动阻力仅增加了1.4倍。

Based on the mechanism of heat transfer enhancement inside porous media,one kind of water cooling heat sink is changed to be a packed heat sink by filling the flow channel with various stainless steel beads.The overall performance of packed heat sinks is compared with that of unpacked heat sink under the same pump power.The results showed that： Over the range of Reynolds number and Prandtl in the experiment,When the Reynolds number and Prandtl are the same,the convective heat transfer coefficient of packed heat sink is 1.2~4.8 times than that of unpacked heat sink and the friction factor of packed heat sink is 1.4~4 times than that of unpacked heat sink.the heat sink filled with Φ4mm perforated stainless steel beads has the best heat chansfer performance,CPU surface temperature is 33 degrees lower than the unpacked heat sink,the convection heat transfer coefficient of packed heat sink is increased 4.8 times,while the flow resistance is increased only 1.4 times.