本論文研究熱管理系統中的熱防護科技，藉由主動式的熱管系統吸收來自外界的高溫熱能，以避免載具有所損壞。開發中高溫迴路式熱管做為中高溫熱防護是本研究的目標，而在熱管系統的設計開發過程中各環節環環相扣，必須挑選合適且相互匹配之工作流體、環路內各元件材質與毛細結構。經文獻指出與實際搭配實驗後，挑選Dowtherm A做為工作流體，管路材料則為不鏽鋼，毛細結構則是經由自行燒結而成的玻璃毛細蕊。實驗結果顯示中高溫迴路式熱管已經成功被開發，此迴路式熱管系統在最大操作瓦數550W下(熱通量：21.38W/cm2)，其蒸發器表面溫度591.9℃，熱阻值為0.93℃/W。此外本研究也針對此系統動態響應、多點熱源模擬進行評估，其研究結果顯示在高低落差瓦數的功率週期測試中，本系統無過衝現象出現。而在多點熱源模擬測試方面，實驗後發現此系統持續進行熱防護工作並且可使蒸發器表面溫度更低。

Aerospace industries are facing the threat of high temperatures at the leading edge during flight. The thermal resistance of vehicle or device structures must be considered with the requirements of high efficiency and high security. Hence, it is necessary to establish a good thermal management system to prevent structure damage. This thesis aims to develop a Loop Heat Pipe (LHP) which is a powerful two phase heat transfer device and can be used in active thermal protection. Dowtherm A was selected as the working fluid and sintered glass wick was placed in the evaporator to provide capillary pumping force. The experimental results show that the intermediate and high temperature LHP has been successfully developed. The evaporator surface temperature is 591.9°C and the system thermal resistance is 0.93°C/ W under the maximum input power 550 watts (heat flux: 21.38W/cm2). In addition, Dynamic tests and multiple heat sources tests are evaluated in the system feasibility study. The results show that the system without overshoot in the power cycling tests (also named as dynamic test). After LHP is facing multiple heat sources, the system stay operates and the evaporator surface has lower temperature.

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