閉迴路震盪式熱管雖具有非常好的散熱效果，但熱傳原理複雜。為了更進一步了解其性質，本實驗以外徑6mm、內徑3 mm 之玻璃管製作9 個折彎總長1980mm 之震盪式熱管，為了使震盪式熱管更容易達到循環，故製作水冷系統並控制溫度在25℃，工作流體使用甲醇。在不同加熱功率 30、60、90、120、150、180W 參數下紀錄溫度和評估熱阻值。利用數位攝影機拍攝影片，分析記錄震盪式熱管內流體作動情形。管內流動模式可分為順轉、逆轉或震盪，由實驗發現，管內流動方向改變與管之溫度有明顯的關係。實驗結果顯示在輸入功率為180W 時，有最低的熱阻值為0.217(K/W)。 A Closed Loop Pulsating Heat Pipe (CLPHP) is a complex heat transfer device with a strong thermo-hydrodynamic coupling governing its thermal performance. This research utilized 6 mm outer diameter and 3 mm inner diameter glass tubes to manufacture 9 turns closed loop Pulsating Heat Pipe(PHP) with a total length of 1980mm. For achieving the loop circulation easily, a water cooling system kept at 25 ℃ was used as the condenser, and used methanol as working fluid. Experiment was conducted to measure temperature difference and to evaluate the thermal resistance under at a series change of power inputs (30W, 60W, 90W, 120W, 150W, 180W). A digital video camera was used to record the working situation of the working fluid inside the channel. The flow pattern can be categorized into clockwise, counter-clockwise and transition status. The results showed the flow direction of PHP was changed with the temperature difference of tubes. The lowest resistance is 0.217(K/W) at an input power of 180W in this study.