本文將進行射出成型之填充過程的水平流場計算，研究其自由液面的形狀變化。為了滿足動態接觸角，我們使用自然三次樣條法對自由液面進行修正，解決接觸線上奇異點的問題。在自由液面的壓力分佈計算上，本文參酌前人所得的自由液面壓力分佈的特性來假設一個壓力分佈方程式，透過四階龍格庫達法來找到壓力分佈對應的自由液面，並利用試誤法修正壓力分佈的係數使其對應的自由液面與流場的自由液面吻合，以此方法來找到正確的壓力分佈之值。同時，我們也可以觀察到不同壓力分佈下自由液面的形狀變化。

To study the change of free surface profile in mold-filling process, we simulating a Horizontal flow field. To ensure the required dynamic contact angle, the liquid meniscus near the wall region is corrected by natural cubic spline and thus successfully removes the stress singularity. We refer to the characteristic of the pressure distribution on free surface postulated by Lee and Liao and suppose a pressure distribution equation on free surface. Using the Runge-Kutta method of order four, the free surface profile corresponding to pressure distribution equation is found. We can correct the parameters of pressure distribution equation to make the corresponding free surface profile fitting the flow field’s free surface profile and if the free surface profile coincided, the pressure distribution is the correct value. Simultaneously, we can observe the change of free surface profile with different parameters of pressure distribution equation.

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