工業上許多製程在進行微小氣泡分析時，都需具明確自由液面位置的氣泡資料，但要得到這些資料目前已被證實相當的困難，造成此困難的原因大致上有兩個，(1)大部分的數值方法若需要準確的自由液面位置來進行計算，經常利用模糊(smearing)邊界的方法來避開因物理性質不連續而難以計算的問題，但此法常導致自由液面處的資料存在不合理之值，(2)流場所需要的表面張力必須由變形後的自由液面來求得，但曲率是二次微分的高階函數，若以形狀來求得曲率會引入過多的雜訊而導致無法計算。目前的數值方法雖然利用了不同的技巧來模擬微小氣泡行為，但對於以上所提出的兩個難點仍無法完善的解決。

本文採用簡單的數值方法，不需模糊自由液面就可以直接進行計算，並利用自由液面不會被流體穿越的特性來求得正確的曲率。相較於目前大部分的研究著重於自由液面邊界的處理方式，本文提出了不同的思考方向，改以直接修正由表面張力所導入的壓力差，希望能解決此類問題的困難之處。

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