本研究使用可視化平板熱管，以甲醇為工作流體，量測分別採用純溝槽毛細、雙層200目燒結銅網、及複合式燒結溝槽/銅網毛細的三種熱管在水平與30°傾角下的性能，並與本實驗室先前以水為工作流體的實驗結果作比較。此外，亦進行液體上升速率實驗來分別量測後兩種結構的毛細滲透性(K)及有效孔徑(rc)。量測實驗顯示複合式燒結溝槽/銅網毛細相較於雙層200目燒結銅網有較大K/rc值，此與其較大的Qmax實驗值相符，顯示兼具銅網高毛細力及溝槽低流阻的複合式毛細優於雙層200目燒結銅網或溝槽毛細。當蒸發區向上傾斜30°，三種毛細皆無法維持低熱阻的穩態操作；相對地，水在90°傾角的複合式毛細中仍能維持穩定操作。此差異可歸因於甲醇較水低的表面張力不足以抵抗重力效應。在共同的測試條件下，優質較高的水比甲醇能達到明顯較高的Qmax。
可視化觀察在單純溝槽毛細及複合式溝槽/銅網毛細實驗中，皆觀察到蒸發區溝槽內的甲醇工作流體有往復式的運動，週期性的回流及退離蒸發區，且複合式毛細因上方銅網提供較大毛細力，有助於工作流體回流蒸發區，使回流的週期短於溝槽毛細，且顯著提升Qmax；甲醇在溝槽毛細與複合式毛細蒸發區內皆未發生核沸騰，但在雙層網毛細中則發生微弱的沸騰現象。相對地，水在三種毛細中均無核沸騰現象。顯示在低壓操作下，以甲醇為工作流體較水易沸騰，但操作極限仍屬毛細限。

This study presents the results of visualization experiments on flat-plate heat pipes with groove wick, 2×200 copper mesh wick, or composite groove/mesh (CGM) wick, using methanol as the working fluid. The operation process of the heat pipe is visualized and the evaporator and condenser resistances are measured under horizontal and 30°-tilted orientations. The present results are compared with the previous study in our lab using water as the working fluid. The permeability (K) and the effective radius (rc) of the CGM wick and the 2×200 copper mesh wick are also measured using the rate-of-rise method. The CGM wick is shown to have higher K/reff than the 2×200 copper mesh wick because of the lower flow resistance in the grooves and the extra capillary force from the sintered mesh. This feature is consistent with the experimental results of higher Qmaxs for the CGM wick than for the 2×200 copper mesh wick. At a 30° inclination, steady state cannot be maintained with low thermal resistances for methanol in all the three kinds of wick. However, water can stably operate in CGM wick at an inclination angle of 90°. This difference can attribute to the lower surface tension of methonal than water. In general, the Qmaxs associated with water, which has a higher figure of merit, are significantly higher than those for methanol under common test conditions.
Visualization reflects the oscillation process in the groove and the CGM evaporator with the wetted region varying periodically. Since the CGM wick provides extra capillary force to draw the working fluid back to the evaporator, the oscillating period appears shorter and the Qmax is larger than those for the groove wick. Weak nucleate boiling is observed only in 2×200 copper mesh wick test. In contrast, no nucleate boiling was observed for water in the three kinds of wick.

目錄
摘要 II
Abstract III
目錄 IV
圖表目錄 VII
符號表 X
第一章 緒論 1
1.1 研究背景 1
1.2 熱管的結構與工作原理 1
1.3 文獻回顧 4
1.3.1 純溝槽毛細結構 5
1.3.2 複合式毛細結構 12
1.3.3 低壓操作狀況下毛細結構中的沸騰現象 23
1.3.4 毛細滲透性之計算 24
1.4 研究動機與目的 29
第二章 實驗設備與方法 30
2.1 可視化平板熱管實驗 30
2.1.1實驗目的 30
2.1.2 實驗設備與架構 30
2.1.3實驗步驟 36
2.1.3.1 前置作業流程 36
2.1.3.2 實驗流程 38
2.1.4 實驗參數與理論分析 38
2.1.4.1 實驗數據計算方式 38
2.1.4.2雙層200目銅網燒結於平滑銅板之毛細熱阻 41
2.1.4.3網/溝槽複合式毛細熱阻 41
2.1.5 實驗誤差分析 42
2.2 毛細滲透性(K)與有效毛細孔徑(rc)之量測實驗 44
2.2.1 實驗目的 44
2.2.2 實驗設備與架構 44
2.2.3 實驗步驟 45
2.2.3.1 前置作業 45
2.2.3.2 實驗流程 46
2.2.4 實驗數據處理 46
2.2.4.1雙層網2×200目毛細 46
2.2.4.2複合式網/溝槽毛細 48
第三章 結果與討論 50
3.1 可視化平板熱管性能測量 50
3.1.1單純溝槽毛細 50
3.1.1.1水平操作狀態下之熱管性能量測 50
3.1.1.2蒸發區朝上傾斜30°量測 53
3.1.2燒結2×200目雙層銅網毛細 53
3.1.2.1水平操作狀態下之熱管性能測量 53
3.1.2.2蒸發區朝上傾斜30°量測 56
3.1.3複合式溝槽燒結單層銅網毛細 56
3.1.3.1水平操作狀態下之熱管性能測量 56
3.1.3.2蒸發區朝上傾斜30°量測 60
3.2水與甲醇為工作流體之比較 61
3.2.1純溝槽毛細 61
3.2.2雙層網毛細 62
3.2.3複合式毛細 63
第四章 結論 65
參考文獻 67

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