超薄平板热管传热性能的实验研究

Experimental study on heat transfer performance of ultra-thin flat heat pipe

随着电子器件的集成度逐渐提高,超薄平板热管作为一种适用于受限空间的高效散热器受到关注。本文对厚度为0.27mm的超薄平板热管进行传热性能的测试,以传热温差、传热量、热阻、等效传热系数作为指标,系统性地研究了加热功率、冷却方式及重力影响下的传热特性。研究发现,重力对超薄平板热管传热性能有轻微影响,竖直状态下的最大散热量较水平状态提高5%~10%,水平较竖直-逆重力状态提高2%~10%。冷却方式对其传热性能影响较大。在较低功率时,相比于自然冷却,强制冷却能使电子元器件在较低温度工作,但造成热管冷热端温差及热阻都比自然冷却条件下大,在超过一定功率(1.2W左右)后,温差及热阻急剧增大,等效传热系数减小,传热效果不佳。

With the gradual improvement of the integration of electronic devices,ultra-thin flat heat pipe has attracted more and more attention as an efficient radiator suitable for confined space.In this paper,the heat transfer performance of ultra-thin flat heat pipe with thickness of 0.27 mm is tested.Taking the heat transfer temperature difference,heat transfer and thermal resistance as indicators,the heat transfer characteristics under the influence of heating power,cooling mode and gravity are systematically studied.It is found that gravity has a slight effect on the heat transfer performance of ultra-thin flat heat pipe.The maximum heat dissipation in vertical state is 5%—10%higher than that in horizontal state,and 2%—10%higher than that in vertical anti-gravity state.The cooling mode has a great influence on its heat transfer performance.At lower power,compared with natural cooling,forced cooling can make electronic components work at lower temperature,but the temperature difference and thermal resistance at the cold and hot ends of the heat pipe are greater than those under natural cooling.After exceeding a certain power(about 1.2 W),the temperature difference and thermal resistance increase sharply and the heat transfer effect is poor.