近年來，電子元件微小化技術不斷進步，使得在相同面積下容納更多的電子元件，因此，單位面積下所產生的熱劇增，這將造成電子產品的散熱問題。本研究即針對雙相移熱的方式，並利用微機電技術設計多平行漸擴微通道(microchannel)使用介電液FC-72(沸點為56℃)於微流道沸騰雙相流散熱技術之研究。
本研究的目的在改善多平行流道入口的設計，並探討漸擴角於沸騰下的效應，進一步提昇多平行漸擴微流道之熱傳能力。研究發現，樹枝狀結構的入口設計能有效的提供流道與流道間均勻的流量分佈，進而提昇最大傳熱量。本研究探討333、666及999 kg/m2s三種以平均流道截面積為基準之質量通率效應。在質量通率為999 kg/m2s的熱傳能力提昇最佳，能提高約35%的臨界熱通率。此外，研究也發現流道漸擴角越大，較能有效的抑止逆流現象的發生；因此，在高質量通率時有較佳臨界熱通率，而在低質量通率時，角度效應對熱傳所造成的影響並不顯著。
本研究證實，多平行微流道輔以適當的入口與漸擴角設計，可具有穩定的高移熱能力。若進一步加深流道，並利用雙入口對流之設計或文獻中之輻射型設計，將可利用熱傳面積倍增的效果滿足現今電子元件高移熱能力的需求。

目錄
摘要…………………………………………………………………………………Ι
誌謝…………………………………………………………………………………Ⅱ
目錄…………………………………………………………………………………Ⅲ
表目錄………………………………………………………………………………Ⅴ
圖目錄………………………………………………………………………………Ⅵ
符號對照表…………………………………………………………………………Ⅸ
第一章 緒論 1
1.1 前言 1
1.2 研究目的 3
1.3 論文架構 9
第二章 文獻回顧 10
2.1 工作流體於沸騰時特性探討 10
2.2 沸騰穩定性探討 16
2.3 流道入口結構影響 19
第三章 實驗設計與熱傳計算分析 21
3.1 實驗環路系統 21
3.1.1 實驗設備環路 21
3.1.2 實驗儀器介紹 22
3.2 測試段流道 26
3.2.1 微流道製作 26
3.2.2 流道製作程序 28
3.2.3 實驗參數 30
3.3 工作流體 33
3.4 實驗流程與方法 35
3.5 熱傳分析 38
3.5.1 能量平衡與熱損估算 38
3.5.2 雙相流熱通率分析 41
3.5.3 熱對流係數分析計算 42
第四章 實驗結果與討論 43
4.1 微流道水力直徑之決定 43
4.2 入口改良對流量分佈影響 45
4.3 雙相流動型態流譜 51
4.4 比較漸擴角度對沸騰熱傳的影響 63
4.5 比較不同入口設計對沸騰熱傳的影響 70
4.6 利用經驗公式比對臨界熱通率 74
4.7 乾化現象 76
第五章 結論 77
5.1 本論文研究成果 77
5.2 未來研究建議 78
參考文獻 82
附錄A實驗數據 87
附錄B系統熱損評估 102

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