U.S.-Japan Cooperative Research: Passive Control of Heat Transfer Performance in Reflux Condensers

该奖项将使香港中文大学的田长霖教授 加州尔湾分校，与香港中文大学 日本东京工业大学等日本研究人员 在两年的时间里。 他们将调查 过程和机制影响的被动控制 性能的设备，如热管，这对操作 基于逆流、两相回流冷凝。 等 被动控制可以通过添加第二组分来实现 热管工作流体;该成分可能是不可冷凝的 气体或工作流体的二元混合物来控制冷凝。 控制气体分布的传热传质机理， 因此热管系统的整体性能，将 分析和实验研究。 的目的 这项研究旨在加深我们对这一现象的基本认识， 其控制热管和类似机构的性能。 对这些现象的充分了解可以促进 热管，这是有限的，即使他们提供了相当大的 在许多应用中优于其他传热方法。到 为了实现这一目标，美国研究人员将分析热传输， 不凝性气体热管的传热性能 热 本文将对二元蒸汽混合物的传热进行实验研究 日本合作者。 通过比较分析和 实验结果，研究人员将共同确定 最有效的工作流体组合。 因此，这项研究 利用互补的分析和实验技能， 美国和日本的调查人员。

This award will enable Prof. Chang-Lin Tien of the University of California, Irvine, to collaborate with Prof. Kunio Hijikata of the Tokyo Institute of Technology, Japan, and other Japanese researchers over a period of two years. They will investigate fundamental processes and mechanisms influencing the passive control of the performance of devices, such as heat pipes, which operate on the basis of counter-current, two-phase reflux condensation. Such passive control may be achieved by addition of a second component to the heat-pipe working fluid; this component might be a noncondensable gas or a binary mixture of working fluids to control the condensation. The heat and mass transfer mechanisms which control gas distribution, and hence overall performance of the heat-pipe system, will be investigated both analytically and experimentally. The purpose of this research is to enhance our basic understanding of the phenomena which control the performance of heat pipes and similar mechanisms. Adequate understanding of these phenomena could stimulate the use of heat pipes, which has been limited even though they offer considerable advantages over other heat-transfer methods in many applications. To achieve this objective the U.S. researcher will analyze the heat-trans- fer performance of heat pipes with noncondensable gases. Heat transfer with binary vapor mixtures will be investigated experimentally by the Japanese collaborator. By comparing the analytical and experimental results, the investigators will jointly determine the most effective combination of working fluids. This research thus utilizes the complementary analytical and experimental skills of the U.S. and Japanese investigators.