一种利用气泡泵效应重力辅助回路热管的实验研究

随着芯片集成度的提高及微型化,为了满足高热流密度电子器件的散热需求,提出了一种利用气泡泵效应重力辅助回路热管,并对其传热性能进行了详细的实验研究.实验中加热功率为21～646W,对应热流密度范围为1.67～51.4W/cm2,采用去离子水为工质.研究结果表明:利用气泡泵效应虽然会增大传输过程的传输热阻,但却能有效增强蒸发腔内扰流,进而增强换热,提高临界换热热流密度;加热功率为646 W时,最小热阻为0.11℃/W;对于本装置,存在一个最佳充液高度,通过观察实验流型图可知,当上升管内为环状流时,充液高度比较合理;蒸发段热阻始终占据总热阻主要部分.研究工作为其在芯片冷却领域的应用打下了良好基础.

Experimental Study on an Thermosyphon Loop with Bubble Pump Effect

An advanced thermosyphon loop using bubble pump effect was proposed in order to meet the need of the chip heat dissipation at high heat flux.The experiment was conducted to investigate the heat transfer performance of the loop with deionized water as the working fluid at the heat load of 21-646 W and the corresponding heat flux of 1.67-51.4 W/cm2.The experimental results show that although the bubble pump effect will increase the heat transmission resistance and but it can effectively enhance the deionized water turbulence in evaporator cavities,leading to the increases in heat transfer capacity and the critical heat transfer heat flux.Moreover,the minimum thermal resistance was 0.11 ℃/W when the heat load was 646 W,and there was an optimum charging liquid level for the loop.In addition,the charging height was reasonable when the flow pattern was annular flow in the ascending tube,and the evaporation thermal resistance was major part of the overall thermal resistance.These results may be beneficial to further research on chip cooling.