開放式脈衝熱管之參數研究與數值模擬

Parameter Research and Numerical Simulation of Open Loop Pulsating Heat Pipe

蕭鳴遠(Ming-Yuan Hsiao)

指導教授 ： 王金樹 ； 林水泉

國立臺北科技大學/機電學院/製造科技研究所/碩士(2006年)

摘要

本篇研究之主旨在研究開放式脈衝熱管(Open Loop Pulsating Heat Pipe)，是由曲折毛細銅管(copper capillary tube)所構成，( ID：1.2mm)，其內部無毛細結構的兩相流開放迴路，期能克服目前對流熱管（Heat pipe）所遇到的熱傳限制與缺點，且因具有構造簡單，製程簡化等優點，是相當具有前景的一種新散熱概念。
本研究建立開放式脈衝熱管之熱模組與製造流程，並且配合實驗室所撰寫之程式來做其性能預測與震動頻率與參數之關係，並利用主動式熱阻量測與被動式熱阻量測，當工作流體為冷媒R134a，得到模組最佳之板厚為4㎜，其操作模式（垂直、水平）不影響其熱性能，最佳填充率在40％，並在管壁的溫度軌跡具有振動週期之現象，而且在Heat Load 280W情況下高H=80模組可得到最低之系統熱阻為0.19(℃/W)，最佳之蒸發長度與冷凝長度比例為高H=80模組，冷卻風量大小對對流熱阻(RC)影響不大，每增加20CFM平均對流熱阻(RC)下降0.01（℃/W），程式模擬實驗模組熱阻平均誤差30％，而能更進一歩瞭解開放式脈衝熱管的整體特性和性能，期待將來更廣泛用在電子產品散熱系統上。

關鍵字

脈衝式熱管 ； 開放迴路脈衝熱管 ； 主動式熱阻量測 ； 被動式熱阻量

並列摘要

The main topic of this thesis is to develop the Open Loop Pulsating Heat Pipe. It is composed of copper capillary tube with inner diameter 1.2mm. The inner structure is used to overcome the current heat transfer difficulty in Heat Pipe. Since it has the advantages in simple structure and simplified fabrication technique, this is a new heat transfer concept.
The research developed an Open Loop Pulsating Heat Pipe module and manufacturing process. The program developing from Lab is also used to predict the performance and the relationship between vibration frequency and coefficients. 「The Active and Passive Thermal testing system of thermal resistance」 are employed in the experiment. When the working fluid is coolant R134a, the optimized thickness of plate is 4mm. The operation modes (vertical/ horizontal) did not affect the heat performance. The optimized ratio is 40%, and periodic vibrations occurred around the heat pipe. When the Heat Load is 280W, and H is 80, the lowest system heat resistance is 0.19(℃/W). The best ratio of optimized vaporizing length and cooling length is for module with H=80 and the magnitude of cooling wind did not affect the convection heat resistance much. Whenever increasing 20CFM, the average convection heat resistances decrease 0.01（℃/W）. The simulation error for the experiment module（H80、FR=60％） is 30%. Thus, we can understand more about the characteristics and performance of the Open Loop Heat Pipe, and hope this research can be employed widely in the future thermal system of electronic products.

並列關鍵字

Pulsating Heat Pipe ； Open Loop Pulsating Heat Pipe ； The Active and Passive Thermal Testing System of Thermal Resistance

參考文獻

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