本研究採用相位場法，以兩相流模擬多個氣泡在固化過程中與固液介面間之動態行為。其中以溫度及相位場函數決定固、液、氣三相。本研究計算質量守恆方程式、動量方程式、能量方程式以及濃度方程式。模擬結果顯示氣泡形狀受對流效應影響及其成長機制極為複雜。

This study applies the phase- field method to simulate multiple pores shapes in solid, and explore mechanisms responsible for pore formation. The simulation method is base on two-dimensional two-phase flow module in the COMSOL software. Conservation equations of mass, momentum, energy and concentration are solved in the entire domain by incorporating with temperature to distinguish solid and liquid phases, and phase field function to distinguish liquid and gas phases. The computed results reveal complicated shapes and mechanisms of the pore shape.

目錄
中文摘要 iii
Abstract iv
目錄 v
圖目錄 vii
符號說明 ix
下標符號說明 xii
第一章 緒論 1
1-1研究背景 1
1-2相位場法(PFM)及二相流(Two phase flow) 1
1-3 研究內容簡介與架構 2
第二章 模型設定與理論之分析 3
2-1模組之統御方程式 3
2-1-1 相位場法方程式 3
2-1-2質量及動量守恆方程式 5
2-1-3 能量方程式 8
2-1-4 濃度方程式 9
2-2模型架構 10
2-2-1 模型架構設定 10
2-2-2 網格分布與設定 11
2-2-3 初始值與邊界設定 12
2-2-4 流體性質 14
2-3 研究模擬之流程圖 15
第三章 結果與討論 16
3-1 模擬條件與說明 16
3-2 基本性質 17
3-3 固化速度低於界面速度 19
3-3-1 密度圖 19
3-3-2 濃度圖 21
3-3-3 溫度圖 24
3-3-4 密度與流場圖 26
3-4 固化速度高於界面速度 29
3-4-1 密度圖 29
3-4-2 濃度圖 30
3-4-3 溫度圖 32
3-4-4 密度與流場等位圖 33
3-5 對流效應 35
3-6 網格驗證 37
3-7 R(0)與壓力關係 39
第四章 結論與未來展望 40
參考文獻 41

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