Experimental study of different charging ratios on operational characteristic of new-type loop heat pipe

doi:10.11949/j.issn.0438-1157.20180504

Abstract

Abstract:

Loop heat pipe (LHP), using the heat of phase change, is a high efficient heat transfer device, which can be applied for the high heat flux components such as CPU, data center, etc. During the operation of LHP, the pressure head due to evaporation cannot be ignored. The LHP is different from the LHP with capillary force, the wick is separated from the heating surface and then a steam chamber is formed, in which the pressure head due to evaporation can be effectively used. The influence of different charging ratios (15%-85%) on the operational characteristic of such a LHP is studied through experiment. The result showed such a LHP can operate in a wide charging ratio (20%-75%) and there existed an optimal charging ratio, which is 35%. Under the optimal charging ratio, the temperature of evaporator bottom was 65.1℃. Through the experimental research of different charging ratios, it can provide reference for the optimization of loop heat pipe design for different heat load heat dissipation and can guide the subsequent experimental research.

Key words: loop heat pipe, pressure head of evaporation, charging ratio, start-up time, thermal resistance

摘要：

环路热管作为一种利用工质相变传输热量的装置，被广泛应用于电子器件散热。研究表明在环路热管运行中，蒸发相变产生的气相压头不能忽略。本环路热管与毛细力热管的区别在于，将吸液芯与蒸发器底板分离，专门形成一个蒸发腔，工质的相变发生在蒸发腔内，以此增大气相压头驱动工质循环。实验研究了在不同灌充率（15%～85%）下的热管运行特性。结果表明：突出气相压头的环路热管可以在较宽泛的灌充率（20%～75%）下正常运行，并且存在最佳的灌充率（35%），可使蒸发器底板温度在65.1℃运行。通过不同灌充率的实验研究，可以为承担不同热负荷散热的环路热管设计优化提供参考，并指导后续的实验研究。

关键词: 环路热管, 气相压头, 灌充率, 启动时间, 热阻

CLC Number:

TK172

ZHU Kai, YANG Zhen, LI Xueqiang, LI Hailong, WANG Yabo. Experimental study of different charging ratios on operational characteristic of new-type loop heat pipe[J]. CIESC Journal, 2018, 69(10): 4246-4252.

诸凯, 杨圳, 李雪强, 李海龙, 王雅博. 不同灌充率对一种新型环路热管运行特性的影响[J]. 化工学报, 2018, 69(10): 4246-4252.

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