震盪式熱管(OHP)是一種利用工作流體相變化進行傳熱的二相流傳熱裝置，本研究利用銅製平板型震盪式熱管(FP-OHP)進行可視化研究，探討其流動現象與熱阻變化。由實驗及流譜觀察得知平板型震盪式熱管系統啟動之輸入熱量，工作流體填充率(FR)25%及50%於輸入熱量120W時順利啟動，熱阻也有明顯驟降的現象；而在填充率75%則需提高輸入熱量到160W才能使系統順利啟動。另外本研究也以並聯熱阻的概念去分析熱傳導途徑，欲從並聯熱阻的概念了解熱通過底下銅材基板傳導與透過工作流體傳導的比例。結果發現計算結果與實驗結果有著符合的趨勢，故得以佐證可利用此理想化假設去進行平板型震盪式熱管熱傳導途徑的分析。並製作不同基板厚度之平板型震盪式熱管，進行實驗量測與熱傳導途徑比例計算，實驗得知基板厚度較薄的Type2 FP-OHP之系統熱阻較高，但其透過工作流體傳遞之熱量比例較高於Type1 FP-OHP。

Oscillating heat pipe (OHP) is a two-phase flow heat transfer device that uses the phase change of the working fluid to transfer heat. This study shows that a copper flat plate oscillating heat pipe (FP-OHP) is used to visualize the flow phenomena and measure its thermal resistance. 25% and 50% of the working fluid filling ratio can be smoothly started, the thermal resistance also significantly decreasing with 120W power input. 75% of filling ratio system won’t be started until input power is increased to 160W.In addition,the concept of thermal resistance in parallel is used to analyze the heat conduction path in this study,and to understand ratio of heat conduction through the copper base plate as well as the working fluid. It can be found that the calculation results have a tendency conforming to the experimental results. Therefore,the ideal hypothesis can be used to make an analysis of the FP-OHP heat conduction path. Next,make the flat plate oscillating heat pipes with different base plate thickness to conduct the experiment and calculate the heat conduction path. It can be found that the Type 2 FP-OHP with a thinner thickness has a higher thermal resistance, but the heat transfer through the working fluid is higher than that of Type 1 FP-OHP.

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