本論文採用相場法(Phase-field method)，以二相流(Two-phase flow)模擬金屬表面受出入口熱通量影響後，其鎔融或固化之暫態熱流行為。本研究考慮統御方程式、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。本篇研究探討熱毛細力所引致表面粗糙度，由不同的邊界條件預測粗糙度變化，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 effects of thermocapillary on surface roughness with different boundary conditions to forecast the disparity of surface roughness. 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
謝誌 ii
中文摘要 iii
Abstract iv
目錄 v
圖次 vii
符號說明 ix
第一章 緒論 1
1.1 研究背景 1
1.2 二相流與相場法(Phase-field method) 1
1.3 研究目的與簡介 3
第二章 理論分析及模型設定 4
2.1 模型統御方程式 4
(A) 質量守恆方程式與相位場法方程式： 4
(B) 動量方程式： 6
(C) 能量方程式： 8
2.2 模型域設定 11
(A) 模型幾何、邊界與網格設定： 11
(B) 各流體性質設定： 14
第三章 模擬結果與討論 15
3.1 模擬條件與說明 15
3.2 模擬結果 15
3.3 結果討論 23
第四章 總結 25
參考文獻 26

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