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传热装置--平行管传热装置（PTH）。PTH具有比先前提出的任何其他热传输装置更高的热传输潜力。本研究的目的是探讨PTH的基本热传输特性，并阐明其热传输机制。第一个试验段有六根铜管。工作介质为R-134 a，管内径为2 mm，管长为100 mm。在这种情况下，通过使热水在蒸发器周围循环来提供热量。第二个试验段有两个（内径为6.5mm和3.5mm）或六个（内径为2.8mm）铜管，以水为工作流体， ...更多信息 D.在第二种情况下，使用电加热器加热蒸发器，并检查倾斜角度、加热速率和管长度的影响。在流动可视化实验中，为了使测试部分能够耐受由R-134 a工作流体引起的高压，通过加工通道（2 mm × 2 mm × 100 mm）并用透明塑料板覆盖，由黄铜板制成测试部分。频道的数量是三个或六个。在六通道测试段的情况下，还通过用具有4 mm的较大边长的通道替换六个通道中的两个通道来检查不同通道尺寸的组合的效果。三通道试验段根据两联箱温差的不同，呈现单向循环流动或振荡流动。在六通道试验段的结果中，通过组合两种通道尺寸，输送的热量增加。本研究所开发之影像处理系统，可撷取多个通道内之上、下向流速及其时间变化，以及流态。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