Vapor-liquid phase change is regarded as an efficient cooling method for high-heat-flux electronic components. The copper-water bent heat pipes are particularly suited to the circumstances of confined space or misplaced heat and cold sources for high-heat-flux electronic components. In this paper, the steady and transient thermal performance of a bent copper-water heat pipe is studied based on a performance test system. The effects of cooling temperature, working conditions on the critical heat flux, and equivalent thermal conductivity have been examined and analyzed. Moreover, the influences of heat input and working conditions on the thermal response of a bent heat pipe have also been discussed. The results indicate that the critical heat flux is enhanced due to the increases in cooling temperature and the lengths of the evaporator and condenser. In addition, the critical heat flux is improved by extending the cooling length only when the operating temperature is higher than 50°C. The improvement on the equivalent thermal by increasing the heating length is more evident than that by increasing cooling length. It is also demonstrated by the experiment that the bent copper-water heat pipe can respond quickly to the variation of heat input and possesses superior transient heat transfer performance.

中文翻译：

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弯曲铜水热管热性能的实验研究

汽液相变被认为是高热通量电子元件的有效冷却方法。铜水弯热管特别适合于空间狭窄或热源和冷源放置不当的情况，以用于高热通量电子元件。本文基于性能测试系统研究了弯曲铜水热管的稳态和瞬态热性能。已经检查和分析了冷却温度，工作条件对临界热通量和等效热导率的影响。此外，还讨论了热量输入和工作条件对弯曲热管的热响应的影响。结果表明，由于冷却温度的升高以及蒸发器和冷凝器的长度增加，临界热通量得到了提高。另外，仅当工作温度高于50°C时，才延长冷却长度来提高临界热通量。与增加冷却长度相比，增加加热长度对等效热量的改善更为明显。实验还表明，弯曲的铜水热管可以快速响应热输入的变化，并具有出色的瞬态传热性能。