在樹脂轉注射出成型充填過程中，樹脂於纖維束內、外的流動模式，直接影響氣泡之生成及位置，亦即影響了產品的品質。本文應用纖維蓆編織的特性，即纖維絲多集中於纖維束內，而纖維束與束之間隙則為無纖維區。因此，在無纖維區(纖維束與束之間隙)可使用Stokes方程式來描述樹脂的流動；而纖維束內，目前國內外研究多使用達西定律(Darcy’s Law)，然而從文獻可知︰由於達西定律缺乏黏滯的剪應力項，因此會與Stokes方程式交界面產生速度不連續情形。因此，本文在纖維束內改使用Brinkman方程式來解決流場速度不連續問題，這是本文與目前國內外研究最大不同。在使用Brinkman方程式和Stokes方程式來求解流場時，由於纖維束內、外樹脂的流速不同，會使流場交界面產生一類似邊界層現象。因此，本文除了將完整模擬纖維束內、外流場運動外，也對樹脂在纖維束內流場形成的邊界層厚度及展開情形做一探討。藉由數值模擬的結果，將可使吾人更深入的了解在轉注成型充填階段，樹脂流動的詳細物理特性及其對成品品質的影響性。 Inside the fiber mats, the gaps between the fiber tows are the fiber free zones. The resin flow through the gap is assumed to obey the Stokes equation. Inside the fiber tows, large of literatures are found to be studied by Darcy’s law, while such a treatment would result in the discontinuity condition in simulated velocity on the interface which were against the gap and the fiber tow. Due to the difference of the velocity inside and outside fiber tows, the interface of the flow field would cause a quasi boundary layer phenomenon. Therefore, we use Brinkman equation instead of Darcy’s law in this study. The method not only simulate the motion inside and outside the fiber tows but discuss the development and formulation of the boundary layer thickness. The results of numerical simulation are convenient and effective in realizing the defect of filling process of Resin Transfer Molding. The physical meanings for such a resin motion and their influences on the quality of product are also discussed.
