輻射型與交錯型蒸發器之迴路式熱管設計

The Radiation and Stagger Loop Heat Pipe Evaporator Design

許超翔(Chao-Hsiang Hsu)

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

本文利用R-134a為工作流體來設計及製造一具平板型蒸發器之迴路式熱管，其不但將毛細結構一體燒結成型於蒸發器底座，可增加其與蒸發器底板的強度並改善傳統迴路式熱管因蒸氣回流至補償室導致系統啟動不易之缺點，而且利用輻射型蒸汽流道可降低蒸氣流阻，達成提高蒸氣循環量，進而降低總熱阻之設計為本設計之特色。
討論迴路式熱管的設計與製造方式，以及系統啟動現象，依照本實驗室『主、被動式熱阻量測』標準流程，量測不同填充率的熱傳量，測試結果顯示本設計與Sinda軟體模擬結果相符合，得到最佳填充率為80％，且本設計輻射型蒸汽溝槽在水平操作下，熱阻值優於傳統型18%，足見輻射型蒸汽溝槽對加快蒸發效率，降低系統熱阻具有相當功效；並針對不同毛細結構(銅粉、鎳粉)、不同冷卻風量(50、70、90CFM)、不同長度傳輸管路(1050mm、1550mm)下，探討其對系統熱阻與對流熱阻影響，得到迴路式熱管在Tj (接點溫度)不超過95℃的條件下，垂直操作狀態最大熱傳量可達300W，系統熱阻值為0.15℃/W，水平操作最大熱傳量250W，系統熱阻值為0.38℃/W。

關鍵字

迴路式熱管 ； 相變化熱傳 ； 蒸汽流道 ； R-134a

並列摘要

This article is using R-134a as the working fluid to design and produce a loop heat pipe (LHP) with a flat evaporator. It not only sinter the wick structure in single process forming at the bottom of the evaporator, but also strengthen the bottom of the evaporator then improve the disadvantage of hard start-up in the system by vapor backflow into compensation chamber in traditional LHP. Moreover, using radiation type vapor groove can lower flux resistance to increase quantity of vapor cycle, and then lower the thermal resistance. Such cogitation is the point of this design.
Discussing the design and producing method of LHP, and start-up in the system, follow the standard process in this laboratory as “Active and Passive Test of Thermal Resistance”, measuring the heat flux in different fill rate, and the test shows the result of this design corresponds with the computer soft "SINDA" simulation, gaining the best fill rate, 80 percent. The radiation type vapor groove in this design under horizontal heat transfer configurations, the thermal resistance is better than traditional type by 18%. It's enough to see that radiation type is efficient in hasten evaporation rate and lower system thermal resistance. Under different wick structure (copper powder and nickel powder), different cooling wind mass (50、70、90CFM), different transmission pipe length (1050mm、1550mm), discuss the influence to the system thermal resistance and convection thermal resistance, it shows that when LHP under the “Junction Temperature” of lower than 95℃, maximum heat transfer can be 300W under vertical heat transfer configurations, and the system (thermal resistance) is 0.15℃/W; Maximum heat transfer is 200W under horizontal heat transfer configurations; system (thermal resistance) is 0.38℃/W.

並列關鍵字

Loop Heat Pipe ； two phase heat transfer ； vapor groove ； R-134a

參考文獻

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