Heat Transport Characteristics and its Mechanism of Heat Transport Device Using Parallel Tubes

cpu功耗的不断增加使得热管理成为其设计中的关键因素之一。本文提出了一种新型的热传导装置——平行管式热传导装置（PTH），该装置由多个毛细管和两端的集管组成。PTH具有比以前提出的任何其他传热装置更高的传热势。本研究的目的是研究甲状旁腺的基本热传输特性，并阐明其热传输机制。在热输运实验中，采用了两种类型的测试截面。第一个测试部分有6根铜管。工作流体为R-134a，管径为2mm，管长为100mm。在这种情况下，热量是通过在蒸发器周围循环热水来提供的。第二个试验段有两根（内径分别为6.5mm和3.5mm）或六根（内径分别为2.8mm）铜管，并使用水作为工作流体。在第二个试验段中，使用电加热器加热蒸发器，并考察了倾角、加热速率和管长对蒸发器的影响。在流动可视化实验中，为了使试验段能够承受R-134a工质所产生的高压，试验段由黄铜板通过2mm × 2mm × 100mm的加工通道制成，并覆盖透明塑料板。频道的数量是三个或六个。在六通道试验段的情况下，通过将六个通道中的两个替换为边长为4mm的较大通道，还检查了不同通道尺寸组合的影响。三通道试验段显示单向循环流动或振荡流动，这取决于两个集管之间的温差。在六通道试验段的结果中，两种通道尺寸的组合增加了传热量。本研究开发的图像处理系统能够捕捉到上游和下游的流速及其时间变化，以及多个通道内的流态。少

The increasing power consumption of the CPUs has made the thermal management one of the critical factors in their design. The present investigators proposed a new type of heat transport device, called parallel tube heat transport device (PTH) consisting of multiple capillary tubes and headers on both ends. PTH has a heat transport potential higher than any other heat transport devices previously proposed. The objective of this study is to examine the fundamental heat transport characteristics of PTH and to clarify its heat transport mechanism.In the heat transport experiments, two types of test sections were used. First test section had six copper tubes. The working fluid was R-134a, and the tube inner diameter and tube length were 2mm and 100mm, respectively. In this case, the heat was supplied by circulating the hot water around an evaporator. Second test section had two (inner diameter of 6.5mm and 3.5mm) or six (inner diameter of 2.8mm) copper tubes and used water as a working flui … More d. In this second case, the electric heater was used to heat the evaporator, and the effects of inclination angle, heating rate, and tube length were examined.In the flow visualization experiments, in order for the test section to be endurable against the high pressure caused by a working fluid of R-134a, the test section was made out of a brass plate by machining channels (2mm x 2mm x100mm) and covering it with a transparent plastic plate. The number of channels was three or six. In the case of six-channel test section, the effect of the combination of different channel sizes was also examined by replacing two channels out of six with those having larger side length of 4mm. Three-channel test section showed the unidirectional circulating flow or the oscillating flow depending on the temperature difference between two headers. In the results of the six-channel test section, the transported heat increased by combining two channel sizes. The image processing system developed in this study can capture the upward and downward flow velocities, its temporal change, and the flow pattern in the multiple channels. Less