本論文主要比較三種不同模組震盪式熱管：未改質純銅震盪式熱管(θ_c≈108°)、全親水改質震盪式熱管(θ_c≈47°)及蒸發段改質親水性表面搭配絕熱段與冷凝段疏水性表面(θ_c≈130°)的混合型改質震盪式熱管。於相同的操作條件下，改變加熱功率，探討表面改質對於震盪式熱管的影響。在實驗結果中發現，未改質純銅震盪式熱管的熱阻值均為三種模組之中最低值；而混合型改質震盪式熱管會在100W時開始由不規則震盪流轉變為單一方向循環流，此時熱阻會開始低於全親水改質。在本研究中，利用溫度數據分析及瞬時頻率強度圖搭配，分析管內的震盪頻率，發現到在未改質純銅震盪式熱管中，震盪頻率皆為三組最高值，推測此種高震盪頻率的傳熱方式，正是未改質純銅震盪式熱管熱阻為最低值的原因。然而對比全親水改質震盪式熱管與混合型改質震盪式熱管，發現到此兩組的震盪頻率是相當的，但是熱阻卻有所差異，因此推測除了震盪頻率是熱傳影響的關鍵外，管內的流譜變化亦會是一個重要的因素。

This paper presents an experimental investigation of whether heat-transfer performance in a closed loop oscillating heat pipe (OHP) would improve if the inner surface has been modified. In this study, three different wettability surfaces of OHP systems have been tested: pure copper surface (θ_c≈〖108〗^°), hydrophilic surface (θ_c≈〖47〗^°) and hybrid OHP with hydrophilic evaporator and superhydrophobic (θ_c≈〖130〗^°) condenser. By increasing heat input, we investigated the thermal resistance of these different modules of OHP. The results show that with the same heat input, the pure copper surface OHP has the lowest thermal resistance; and the pure copper surface OHP has the highest frequency among the three types. It seems that the method of the surface modification in this paper would reduce the frequency of the OHP system; nevertheless, if we compare the hydrophilic surface OHP and the hybrid OHP, when the heat input reached 100W, the hybrid OHP has lower thermal resistance than the hydrophilic surface one. This is because when heat input reached 100W, the flow pattern in the hybrid OHP would change from oscillation to circulation.

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