近年來隨著科技的進步，電子元件開始朝向微小化、密集化及快速的運轉效能來發展，這使得單位體積的電子元件，其內部的發熱密度大幅上升，因此如何在有限空間內將熱量移除是現今面臨的ㄧ大課題。早期的散熱技術主要依賴單相的自然對流及強制對流，現今則多仰賴雙相沸騰熱傳之高熱傳遞性，得到高效率的散熱效果。
核沸騰熱傳因其熱傳機制相當複雜，使其具備高熱傳遞之特性，從加熱面傾斜角的方面來看，核沸騰之熱傳情況會因其加熱壁面傾斜角的不同使得熱通量及表面過熱度有所變化，也因此在微電子元件的散熱研究上，傾斜角效應是所需考慮的重要因素。從汽泡脫離的現象來看，在狹小的空間環境裡，隨著熱通量的提升，汽泡脫離直徑也會隨之增加，當脫離的汽泡大到足以填滿狹小空間時，則會造成液體難以補充至加熱表面，而產生乾化之現象，導致電子元件的燒毀，由此可知，汽泡脫離的現象在散熱技術的研究上有著相當大的意義。
本論文之研究以實驗方式進行，探討在不同加熱面傾斜角的情況下，其對於熱通量與表面過熱度之影響，並藉由高速攝影機觀察核沸騰過程中汽泡脫離之現象，透過影像分析得到主導汽泡脫離現象的三個主要參數: 有效成核址密度(Nucleation site density)、汽泡脫離直徑(Bubble departure diameter)及汽泡脫離頻率(Bubble departure frequency)。

In recent years, with the ever-changing nature of technology, the electronic components develop toward miniaturization, concentration, and high operational efficiency. This fact makes the heating density inside the electronic components increase significantly. Thus, there is a problem about heating dissipation inside a narrow space.
Nucleate pool boiling is an effective phenomenon of heat transfer. It is composed of many complicated boiling mechanisms. This fact makes it has a very heat transfer coefficient. The heat transfer coefficient of nucleate boiling vary with the heater surface conditions, such as orientation, size and working fluids. The surface orientation is an important parameter on the heat dissipation technology.
The purpose of the present study is to clearly understand the influence of heater orientation on nucleate pool boiling. The photograph of bubble behaviors will be shot by high speed camera to analyze the parameters which took the lead on nucleate pool boiling: Nucleation site density, Bubble departure diameter, and Bubble departure frequency.

摘要 i
Abstract iii
圖目錄 vi
表目錄 x
符號對照表 xi
第一章 緒論 1
1-1.研究背景 1
1-2.研究目的 2
第二章 文獻回顧 3
2-1.核沸騰實驗回顧 3
2-2.核沸騰模型回顧 10
第三章 實驗操作及設備 20
3-1.實驗研究方法 20
3-1-1.溫度量測 20
3-1-2.熱通量及表面過熱度之計算 20
3-1-3.成核址密度計算 21
3-1-4.汽泡脫離頻率計算 21
3-1-5.氣泡脫離尺寸計算 22
3-2.實驗環路及設備 23
3-2-1.濾水系統 23
3-2-2.預熱及除氣系統 24
3-2-3.加熱系統 25
3-2-4數據擷取分析系統 35
3-3.實驗步驟 37
3-3-1.前置作業 37
3-3-2.沸騰實驗 38
3-3-3.後端處理 38
3-4.實驗SOP流程圖 40
第四章 誤差分析 41
第五章 結果與討論 46
5-1.實驗之可重複性 46
5-2.角度對於核沸騰熱傳能力之影響 49
5-3.角度對於汽泡動態行為之影響 56
5-3-1.角度對於成核址密度之影響 56
5-3-2.角度對於汽泡脫離直徑之影響 57
5-3-3.角度對於汽泡脫離頻率之影響 67
第六章 結論 69
參考文獻 70

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