摘要
本研究為觀測噴霧液滴對熱板的冷卻行為，藉由加壓液體之壓力產生不同之流量，實驗觀察不同We數及液體過冷溫度對噴霧液滴冷卻熱板行為的影響。固定噴嘴口與加熱平板之間的距離及噴霧錐角之狀態下，將單佈性單霧噴在加熱平板上，並記錄加熱平板面上之溫度變化，採用兩種實驗方法：(1)穩態 及 (2) 暫態，分別描繪出沸騰曲線圖和冷卻曲線圖。經由實驗求出各種噴霧行為下之qCHF值及冷卻現象。改變之參數為：韋伯數(Water：80、148、231，R-134a：50、96、152)、液體壓力(0.1MPa、0.15MPa、0.2MPa)、液體過冷溫度(Water：55℃、60℃，R-134a：2℃、4℃)、暫態實驗之初始板溫(Water：240℃，R-134a：60℃)。最終目標希望能夠對噴霧冷卻之熱傳現象有全盤且更深入之了解，以建立更完整之學理基礎，提供學術界作為參考。

Abstract
Spray cooling is frequently encountered in a number of engineering applications. An experimental study was made to investigate the effect of liquid sprays used to cool a hot surface. Both pure water and R-134a were served as a working medium sprayed from a single circular nozzle onto a Pt plated surface of an electrically heated surface. Spray cooling tests were performed for steady state and transient experiment. Cooling characteristics curves were obtained over a range of Weber number(Water：80、148、231，R-134a：50、96、152),pressure drop of liquid(0.1Mpa、0.15Mpa、0.2Mpa),degree of subcooling (Water：55℃、60℃，R-134a：2℃、4℃) and initial temperature(Water：240℃，R-134a：60℃). Thermal design data of high performance as well as more and further physical insight of the above-stated spray cooling heat transfer can be acquired. The results will hopefully be helpful not only for the academia but for the industry.

目錄
目錄 I
圖目錄 Ⅳ
表目錄 Ⅵ
符號說明 VII
中文摘要 Ⅸ
英文摘要 Ⅹ

第一章 緒論 1
1-1 前言 1
1-2 背景與目的 1
1-3 文獻回顧 3
1-4 研究範圍 7

第二章 實驗設備 9
2-1 噴霧系統 9
2-2 壓力控制系統 9
2-3 測試容器 9
2-4 加熱系統 10
2-4-1 加熱器(一) 10
2-4-2 加熱器(二) 10
2-5 冷卻系統 11
2-5-1 ?皕聾蘛? 11
2-5-2 凝結器 11
2-6 影像擷取系統 11
2-7 溫度量測儀器 11

第三章 實驗方法及步驟 20
3-1 實驗方法 20
3-1-1 穩態 20
3-1-2 暫態 20
3-2 流量控制 21
3-3 溫度量測 21
3-4 SEM觀測 21
3-5 實驗步驟 22
3-5-1 清洗 22
3-5-2 測漏 22
3-5-3 測試區設定 22
3-5-4 液晶校正 23
3-5-5 穩態實驗 24
3-5-6 暫態實驗 25
3-6 數據處理 27

第四章 數據分析 28
4-1 韋伯數定義及計算 28
4-2 質量流率計算 28
4-3 相關計算 29
4-3-1 穩態實驗 29
4-3-2 暫態實驗 30
4-3-3 液晶局部熱傳係數 31

第五章 誤差分析 34

第六章 結果與討論 36
6-1 穩態曲線 36
6-2 穩態熱傳效率 37
6-3 暫態曲線 37
6-4 液晶分析 38
6-5 噴霧冷卻經驗公式 38

第七章 結論與建議 52
7-1 結論 52
7-2 建議 52
參考文獻 54
附錄A 62

圖 目 錄
圖2-1 噴嘴圖示 13
圖2-2 實驗迴路示意圖 14
圖2-3 實驗測試系統圖 15
圖2-4 加熱器(一)構造圖 16
圖2-5 加熱器(一)液晶塗佈圖 17
圖2-6 加熱器(二)構造圖 18
圖2-7 測試系統實體圖 19
圖4-1 平板質量通量圖 33
圖6-1 冷媒R-134a穩態沸騰曲線圖 39
圖6-2 純水穩態沸騰曲線圖 40
圖6-3 沸騰熱傳係數圖 41
圖6-4 冷媒R-134a相對沸騰曲線圖 42
圖6-5 純水相對沸騰曲線圖 43
圖6-6 冷媒R-134a冷卻曲線圖. 44
圖6-7 純水冷卻曲線圖 45
圖6-8 最高熱通量(CHF)與質量流率關係圖 46
圖6-9 最低熱通量(MHF)比較圖 47
圖6-10 噴霧冷卻經驗公式圖 48
圖6-11 液晶細部熱傳係數圖 49
圖6-12 SEM觀測白金(Pt)表面圖 50
圖6-13 冷媒R-134a與純水之噴霧冷卻影像圖 51

表 目 錄
表1-1 實驗參數表 8
表5-1 誤差表 35

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