本研究採用相位場(Phase-field)方法模擬氣泡在固化過程的固液界面之行為。流場以質量、動量、能量等方程式模擬氣泡之變化。此模式考慮固、液、氣三相共存，不同之流體在密度和黏滯係數，外力則考量表面張力和重力的作用。此外，界面之質量交換也不可忽略。結果顯示固化速度快時產生氣孔，固化速度慢時氣泡漂離

The study uses the Phase-field method to simulate the bubble behavior of liquid-solid interface in the solidification.The flow use the mass equation,momentum equation,and energy equation for simulating the variation of bubble. This pattern considers that three-phase of solid, liquid,and gas coexist with the different density and viscosity coefficient,and the external force considers surface tension and the gravity force. In addition,the mass transfer also can’t neglect around interface. The result discuss the production of pore when the velocity of solidification is fast,but bubble leaves when the velocity of solidification is slow.

謝誌 Ⅰ
目錄 Ⅱ
圖目錄 Ⅳ
符號說明 V

中文摘要 VII

英文摘要 VIII

第一章　緒論 1
1.1 前言與文獻回顧 1
1.2 相位場模組(PFM) 2
1.3 研究內容簡介 3
1.4 本文架構 3
第二章　系統模型之假設與理論分析 4
2.1 理論模型與假設 4
2.2 相位場模組 5
2.3 動量＆質量守衡方程式 7
2.4 能量守衡方程式 9
2.5 邊界條件 10
第三章　結果與討論 12
3.1 溫度梯度大時的結果 12
3.2 溫度梯度小時的結果 16
第四章　結論 20
參考文獻 21

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