Abstract As technology becomes increasingly miniaturized, extremely localized heat dissipation (so called hot-spots) leads to the challenge of how to keep these devices from overheating. Heat dissipation from advanced power and military electronics is expected to be on the order of 1 kW/cm2, while conventional cooling techniques can only cool up to 10 W/cm2 with forced air convection cooling and 500 W/cm2 with advanced microchannel liquid cooling. In the present study, we propose and investigate a novel radial pulsating heat-pipe (RPHP), which is tailored for effective “spreading of heat” from a local high heat-flux heat source. An experimental system for RPHP was constructed with a 110 mm diameter circular brass plate with 1 mm depth and 1 mm width primary channels. The primary channels are enclosed using a polycarbonate cover that is equipped with an internal working fluid charging port. The diameters of the boiling chamber (or evaporator section) and the condenser section were 10 mm and 60 mm, respectively. Thermocouples were installed to measure the temperatures of RPHP surface and the working fluid. The pressure of the fluid in the boiling chamber was measured using an absolute pressure transducer. The measured data was used to evaluate the thermal performance of the RPHP in terms of convective heat transfer coefficient and thermal resistance with respect to working fluid fill ratio and power input. The study showed that the system was effective at spreading locally concentrated heat; in the study the heater temperature was dropped by 23 °C compared to that of pure heat conduction through the RPHP body in 30 W heater power case.

中文翻译：

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用于高热通量热扩散的新型径向脉动热管

摘要 随着技术变得越来越小型化，极其局部的散热（所谓的热点）导致了如何防止这些设备过热的挑战。先进电源和军用电子设备的散热量预计约为 1 kW/cm2，而传统冷却技术在强制空气对流冷却时只能冷却至 10 W/cm2，在先进微通道液体冷却时只能冷却至 500 W/cm2。在本研究中，我们提出并研究了一种新型径向脉动热管 (RPHP)，该热管专为局部高热通量热源的有效“传热”而设计。RPHP 的实验系统由直径 110 毫米的圆形黄铜板构成，主通道深度为 1 毫米，宽度为 1 毫米。主要通道使用配备内部工作流体加注口的聚碳酸酯盖封闭。沸腾室（或蒸发器段）和冷凝器段的直径分别为 10 mm 和 60 mm。安装热电偶以测量 RPHP 表面和工作流体的温度。使用绝对压力传感器测量沸腾室中流体的压力。测量数据用于评估 RPHP 在对流传热系数和热阻方面的热性能，相对于工作流体填充率和功率输入。研究表明，该系统能有效地分散局部集中的热量；