本計劃有系統定量的探討雷射或電子束製造加工，與工件固化後表面瑕疵形態，譬如表面湧起、凹陷，或漣漪形成之機構；此等瑕疵經常伴隨著氣孔、下切、成分偏析，與應力集中等，直接影響表面熱處理與銲接成品品質。為了促進品質確定重複性，及增加大量生產能力減少成本，必須瞭解瑕疵產生之機構。雖然過去從事表面瑕疵之研究不少，但是有系統，深入定量地從熱科學、物理，形態選擇學觀點探討極為有限。由於過程複雜，本研究考慮質量、動量及能量方程式，並引進介面與運動邊界條件，以計算熱毛細力、蒸發、固液、氣液相變化以模擬真實過程。

Surface patterns of bead defects such as humping, gouged and rippling after solidification during laser and electron processing and different welding processes are systematically and quantitatively studied in this project. These defects usually accompanying with porosity, undercut, segregation, stress concentration, etc. seriously reduce the properties and strength of the surface heat treatment and weld joint. In order to improve quality, assure mass production and repeatability and reduce costs, it is necessary to understand their mechanisms. Although the defects have been extensively studied in the past, systematical, penetrative and quantitative understanding of their formation from thermal, physics, and pattern selection viewpoints are limited.The study include thermocapillary force, evaporation, and phase changes between solid-liquid and liquid-gas phases by introducing energy equation and interfacial and kinematic boundary conditions to simulate realistic processes.

目錄
頁次
謝誌 I

目錄 II

圖表目錄 IV
符號說明 V
中文摘要 VIII
英文摘要 IX

第一章　緒論 1
　　　1.1 研究目的與簡介 1
　　　1.2 二相流與相場法(Phase-field method) 1

第二章　理論分析與模型設定 4
2.1 模型統御方程式 4
(A). Mass conservation Equation & Level-set equation 4
(B). Momentum Equation 6
(C). Energy Equation 8
　　　2.2 模型域設定 10
(A)模型幾何、邊界與網格設定 10
(B)各流體性質設定 13
第三章 模擬結果與討論 14
第四章 總結 17
參考文獻 18

參考文獻
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