Dual compensation chamber loop heat pipe (DCCLHP) is a promising technology for future avionics cooling. In this work, the effect of orientations on the steady state and startup performance of a DCCLHP with kW class heat transfer capacity was investigated experimentally. Experimental results show that for high capacity DCCLHP, the variation of condenser performance at different orientations is a decisive factor in system performance, which could result in up to a 50 % decrease or 10 % increase in the heat transfer limit. In addition, the lack of condenser performance could also have a potential negative impact on the startup performance. By establishing a method to analyze the operating temperature, the authors provided an in-depth analysis of the related mechanisms. The effect of gravity could change the force condition and therefore the thickness of the condensate in the condenser, which in turn affects the condenser capacity and the working fluid temperature flowing into the compensation chamber. As a result, for practical applications, it is necessary to focus on the installation of the condenser to avoid the orientations that tend to cause the increase in the thickness of the condensate film, such as the condensate flow inside the condenser was opposite to gravity. The research content of this paper could deepen the understanding of LHP technology and contribute to the realization of application in acionics cooling in the future.

中文翻译：

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大容量双补偿室环路热管不同方向的实验研究

双补偿室环路热管（DCCLHP）是未来航空电子设备冷却的一项有前途的技术。在这项工作中，通过实验研究了取向对具有 kW 级传热能力的 DCCLHP 的稳态和启动性能的影响。实验结果表明，对于高容量 DCCLHP，不同方向的冷凝器性能变化是系统性能的决定性因素，这可能导致传热极限降低 50% 或增加 10%。此外，冷凝器性能的缺乏也可能对启动性能产生潜在的负面影响。通过建立分析工作温度的方法，作者对相关机制进行了深入分析。重力的作用会改变力的条件，从而改变冷凝器中冷凝水的厚度，这反过来又影响冷凝器的容量和流入补偿室的工作流体温度。因此，在实际应用中，需要重点关注冷凝器的安装方向，避免容易导致冷凝液膜厚度增加的方向，例如冷凝器内部的冷凝水流动方向与重力相反。本文的研究内容可以加深人们对LHP技术的理解，并有助于未来实现其在离子冷却中的应用。