應用於迴路式熱管高分子毛細結構之製造研究

Manufacturing and Investigation of the Polymer Wick Structure Applied to Loop Heat Pipe

王鵬凱(Perng-Kae Wang)

指導教授 ： 陳瑤明

國立臺灣大學/工學院/機械工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01890

摘要

高分子毛細結構具有高孔隙度、低熱導係數與製作成本低廉等優點，而目前將高分子毛細結構應用於迴路式熱管的相關研究並不多見，因此本文旨在建立可應用於迴路式熱管高分子毛細結構之設計、製造及測試能力。依照迴路式熱管在操作時的限制與特性，選擇聚苯乙烯作為毛細結構的材料，以鹽溶濾法(salt leaching)來製作高分子毛細結構。製作過程中遭遇到氯化鈉粉末聚集與熱壓填料的幾何尺寸效應等問題，在文中提供一個較佳的解決方式。在製作出高分子毛細結構後，量測其各項參數包括孔隙度、有效孔徑與滲透度，並將高分子毛細結構置入迴路式熱管中，進行熱傳性能測試。
本實驗經由實際量測以鹽溶濾法製作出來的毛細結構，其有效孔徑約在12~13 之間，孔隙度可控制在65~78%，綜整不同孔隙度的高分子毛細結構其滲透度後，找出滲透度與孔隙度相關的經驗公式，將有助迴路式熱管的熱傳性能預測。將孔隙度65%、滲透度 的高分子毛細結構置入迴路式熱管中，進行熱傳性能測試，在容許溫度50℃與熱沉溫度10℃下，最高熱傳量可達200 W，熱阻為0.177℃/W。

關鍵字

鹽溶濾法 ； 高分子毛細結構 ； 迴路式熱管

並列摘要

Polymer wick structure has the advantages that include high porosity, low thermal conductivity coefficient and lower manufacturing cost etc. However the relative researches on applying the polymer wick structure to LHP is still not familiar to date. Hence, the present effort seeks to set up the design, fabrication and test capacity of the polymer wick which is applicable to LHP. Based on the operating limitation and characteristics of LHP, polystyrene is chosen as the material and the polymer wick structure is fabricated by salt leaching method. Here, obstacles arising in the clustering of sodium chloride powder and the geometry effect of the filling material used during hot pressing process are solved. Besides, after the polymer wick structure is made, the wick parameters that include pore size, pore radius and permeability are measured. The wick is then installed into a LHP, and the heat transfer performance of LHP system is tested.

The testing results show that, the pore radius lies in between 12~13 , and the porosity can be controlled within the range of 65~78%. Summarizing the permeability of the polymer wicks with different porosity, a formula between permeability and porosity expressed as is established. The formula would help the prediction of the heat transfer capacity of LHP. Finally, a polymer wick with the porosity of 65%, pore size 12.5 and the permeability of is installed into a LHP system, and the performance test is conducted under the operating temperature of 50℃ and the heat sink temperature of 10℃. The results show that, the maximum heat transfer capacity of present LHP system approaches 200W, and the thermal resistant is 0.177℃/W.

並列關鍵字

salt leaching ； lop heat pipe ； polymer wick

參考文獻

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