本研究使用相位場方法模擬氣泡在固化過程中與固液介面間之動態行為。本模式為二相流模組，以溫度及相位函數決定固、液、氣三相存在比例。統御方程式為包含相百分比性質之質量(mass equation)、動量(momentum equation)、能量方程式(energy equation)。計算結果顯示表面張力與溫差大小影響氣泡形狀與固化速度。

The study applies the phase-field method to simulate the behavior between bubble and liquid-solid front in the solidification. During the process, the two-phase flow module is used to match up with temperature and phase-field function to determine the percentage of- solid, liquid, and gas- in the domain. The governing equations for mass, momentum and energy contain coefficients which are related to percentage of phases.The result show that the surface tension and the temperature difference will influence the shape of bubble and the velocity of solidification.

謝誌 i
中文摘要 ii
Abstract iii
目錄 iv
圖目錄 vi
符號說明 viii
下標符號說明 ix
第一章 緒論 1
1.1 前言與研究背景 1
1.2 相位場法(PFM)及二相流(two phase flow) 3
1.3研究內容簡介與架構 4
第二章 系統模型設定與理論之分析 5
2.1 模組之統御方程式 5
(A) 質量守恆方程式 & 相位場方程式 5
(B) 動量方程式 6
(C) 能量守恆方程式 10
2.2 模型設定與邊界假設 11
第三章 結果與討論 14
3.1 上下邊界溫差734K 14
(1)固化之情形與氣泡變動圖 14
(2) 速度場之r分量 16
(3) 速度場之2-D圖 17
(4) 等溫線 19
3.2 重力場造成之影響 21
3.3 接觸角造成之影響 23
3.4 上下邊界溫差變小(434K) 25
3.5 討論 27
第四章 結論 28
參考文獻 29
附錄 32

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