應用於迴路式熱管之高分子毛細結構參數探討

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

林俊宇(Jun-Yu Lin)

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(2006年)

https://doi.org/10.6342/NTU.2006.01870

摘要

本論文研究高分子毛細結構參數對迴路式熱管熱傳性能之影響；毛細結構參數包括有效孔徑、滲透度與孔隙度，其參數為影響迴路式熱管性能之重要關鍵，因此找出參數彼此間之關係，將有助於迴路式熱管設計及性能提昇。目前毛細結構多以金屬粉末燒結，金屬毛細結構應用於迴路式熱管系統時，因金屬材料熱導係數高易有熱洩漏問題，且在燒結製程中毛細結構參數不易控制，因此本論文選擇低熱導係數的高分子-聚苯乙烯作為毛細結構材料，並利用生醫領域中鹽溶濾法製作高分子毛細結構，藉由調控氯化鈉粒徑大小及其在高分子材料中之比例，以控制有效孔徑與孔隙度參數，進而探討孔隙度、有效孔徑與滲透度三者參數之關係。本實驗經由實際量測以鹽溶濾法製作之高分子毛細結構，其有效孔徑可控制在 之間、孔隙度可控制在49~78%之間，搭配不同實驗參數，找出滲透度與孔隙度之相關經驗公式 ，將有助於迴路式熱管設計及探討毛細結構參數對熱傳性能之預測。
實驗結果顯示，當有效孔徑越小、孔隙度越大時，其熱傳性能越好，故將平均有效孔徑 、孔隙度78%與滲透度 的毛細結構置入迴路式熱管中進行熱傳性能測試，並與具金屬毛細結構迴路式熱管作熱傳性能比較。在蒸發器容許溫度85℃條件下，具金屬毛細結構迴路式熱管熱傳量為100瓦時，熱阻值為0.711℃/W；具高分子毛細結構迴路式熱管熱傳量可達180瓦，其熱阻值為0.408℃/W。相較可知具高分子毛細結構迴路式熱管其熱傳性能可提昇80%。高分子毛細結構相較於金屬毛細結構，在製作特性上具有製作成本低、參數易控制與加工性佳等優點，將有助於提昇迴路式熱管的應用潛力。

關鍵字

聚苯乙烯 ； 鹽溶濾法 ； 迴路式熱管

並列摘要

The research focuses on the influence of the parameters in polymer wick structure to the performance of the heat transfer in LHP. The parameters on polymer wick structure, including pore radius, permeability and porosity, would promote the design and the qualities and capabilities of LHP. At present, lots if wick structures sinter with the metal powder. When the metal wick structure uses in LHP, the high thermal conductivity coefficient in the metal material causes the problem of the heat transpiration easily, and it is difficult to control well in the parameters of polymer wick structure in the progress. Therefore, polystyrene which is low thermal conductivity coefficient is chosen as the material, and the polymer wick structure is fabricated by salt leaching in biotechnology area. Then, adjusting the size of sodium chloride powder and its percentage in the material, it could not only control the parameter efficiently between the pore radius and the porosity, but also be discussed the relationship of the parameter deeply among pore size, pore radius, and permeability. The experiment is the polymer wick structure is fabricated by salt leaching. The results of the test show that the pore diameter lies in between and , and the porosity is able to be controlled within the range, form 49% to 78%. With different parameters, a formula between permeability and porosity expresses as . Furthermore, this formula would promote both the design of LHP and the prediction of the performance of the heat transfer in the parameter of the wick structure.
What the results of the test reveal is when the smaller the pore radius is, and the bigger the porosity is, the performance of the heat transfer would be much better. Hence, a wick structure with the pore size of , the porosity of 78%, and the permeability of is installed into a LHP system to carry out the test of the performance of the heat transfer. In addition, the above test would compare with the performance of the LHP with a metal wick structure. As the performance test is conducted under the operating temperature of 85℃, and the capacity of the heat transfer in LHP with the metal wick structure approaches 100W, the thermal resistant is 0.711℃/W. however, under the same operating temperature, the maximum capacity of the heat transfer in LHP with polymer wick structure would approach 180W, and its thermal resistant is 0.408℃/W. as a result, with the above comparison, the performance of the heat transfer in LHP with polymer wick structure can increase almost 80%. In short, polymer wick structure, comparing with metal wick structure, has some advantages in the characteristics in its production, such as low manufacturing cost, easy-controlled parameters, perfect processing, and so forth. Moreover, these merits would promote the potential of LHP as much as possible.

並列關鍵字

polystyrene ； salt leaching ； loop heat pipe

參考文獻

王鵬凱, “應用於迴路式熱管高分子毛細結構之製造研究,” 國立台灣大學碩士論文, 2004.

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