本論文採用相場法，以二相流模擬金屬表面受出入口熱通量影響後，所產生鎔融或固化之暫態熱流行為。本研究考慮質量守恆方程式、動量方程式、能量方程式與等位函數，求得模擬流場的溫度、壓力、流線與等位數之分佈。本篇研究探討介於融化區與未融化區之角落流，由不同的邊界條件預測角落流體變化，譬如固化、湧起、渦流或漣漪形成 ，結果顯示表面張力與溫度梯度所產生的熱毛細力為融區之驅動力。

This thesis implicates the use of Phase-field method, to create a simulation of the transient thermal of the surface of a metallic material, molten or solidified by the heat flux during process. The project itself is considered acquainted with mass conservation equation, momentum equation, energy equation and level-set equation. In order to reach the results within the flow field domain, temperature, pressure, streamline and level-set number. This research is about the changes of corner flow between fusion area and solid area, uses different boundary conditions to forecast the disparity of corner field change. Such as solidified, surface fill, whirlpool phenomenons or the formation of ripples. In add, the results will display the area where flows of the molten are forced by thermocapillary. Which is caused by surface tension and temperature gradient.

論文審定書 ....................................................................................................................... i
誌謝 ................................................................................................................................... i
中文摘要 ........................................................................................................................... i
Abstract ............................................................................................................................ iv
符號說明 .......................................................................................................................... v
目錄 ............................................................................................................................... viii
圖次 .................................................................................................................................. x
第一章 緒論 .................................................................................................................... 1
1.1 研究背景 ........................................................................................................... 1
1.2 二相流、相位場法模擬方法簡介 ................................................................... 1
1.3 本論文研究內容簡介 ....................................................................................... 2
1.4 論文架構 ........................................................................................................... 3
第二章 .............................................................................................................................. 4
2.1 模型之統御方程式 ............................................................................................ 4
2.1.1 相位場法方程式 ..................................................................................... 4
2.1.2 質量守恆方程式 ..................................................................................... 5
2.1.3 動量方程式 ............................................................................................. 6
2.1.4 能量方程式 ........................................................................................... 12
2.1.5 濃度方程式 ........................................................................................... 13
2.2 模型區域設定 .................................................................................................. 14
2.2.1 模型幾何 ............................................................................................... 14
2.2.2 模型網格分佈 ...................................................................................... 15
2.2.3 模型區域邊界設定 ............................................................................... 16
ix
2.2.4 初始值設定 ........................................................................................... 18
2.2.5 各流體性質 ........................................................................................... 19
2.2.6 研究模擬之流程圖 ............................................................................... 20
第三章 模擬結果與討論 .............................................................................................. 21
3.1 模擬條件與說明 ..................................................................................... 21
3.2 基本性質模擬圖 ...................................................................................... 21
3.3 模擬結果與討論 ..................................................................................... 26
第四章 結論 .................................................................................................................. 33
參考文獻 ........................................................................................................................ 34

參考文獻
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