震盪型熱管(Oscillating Heat Pipe, OHP) 為一非常具有前景的新型兩相流熱傳裝置，其具有構造簡單、熱傳量大且無須毛細結構即可作動等特點。本研究主旨在於利用銅表面改質技術將震盪式熱管內壁改質為表面接觸角大於150 度之超疏水表面，探討此種改變對系統效能所產生的影響。本研究所使用之閉迴路震盪型熱管(Close Loop OHP,CLOHP)由內徑2 mm、外徑3 mm 之銅管製作而成，固定填充比率為 50%，工作流體使用乙醇或水。研究中首先以未表面改質OHP 系統進行效能與操作極限之測試，再配合全尺寸可視化系統進一步了解OHP運作情形，最後將OHP 系統內壁表面改質為超疏水表面，並測試其性能與未改質系統性能相比較。結果顯示系統震盪行為會受表面接觸角與傾斜角影響，而超疏水內壁將促使系統內部流體產生單方向系統循環，另外推測系統藉由循環與冷凝行為由膜式冷凝轉為滴式冷凝而有效提升系統熱傳效率約10%。

Oscillating heat pipe (OHP) is a new type of two-phase heat transfer device which has the characteristics of simple construction, high heat flux capability and no need of wicking structures for liquid transport. The purpose of this study is using surface modification to fabricate a super-hydrophobic OHP system which has contact angle over 150∘and
investigates its effects on its system performance. The closed-loop oscillating heat pipe is designed by using 2mm ID and 3mm OD copper tubes. The filling ratio is fixed at 50%. Working fluid is using ethanol or DI water. In this study, the performance and operating limit of the OHP system
is firstly tested without surface modification. A full-size OHP visualization model is also constructed to visualize the flow behaviors. Finally the super-hydrophobic OHP system is tested. The results show that the system oscillating behavior is related to inner wall contact angle and sysem tilting angle, the inner flow field of OHP system with super-hydrophobic surfaces has a trend to circulate in one direction. In addition, the reason of heat transfer enhancement is suspect that the motion of condensation changing from filmwise condensation to dropwise condensation, heat transfer efficiency of super-hydrophobic OHP system can be enhanced about 10%.

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