近年來，模流分析中將整組模具轉換為實體網格之需求日漸增多，以獲得更趨近於真實情況之各項模擬數據。然而，整組模具網格化需要耗費更多的時間，主要原因為CAD模型前處理工作費時。此外，若因產品CAD模型設計不良，導致需反覆修改時，將更增加作業的時間。本計畫擬針對射出成型模具之CAD模型前處理需求，探討｢特徵參數優化與幾何設變技術｣及｢整組模具之關聯性孔洞辨識與簡化｣，前者可檢視CAD模型特徵設計之正確性，後者則簡化整組模具CAD模型之孔洞，兩者均可促進模流分析流程的效能。在｢特徵參數優化與幾何設變技術｣方面，首先由肋特徵資料進一步分類與篩選，依據不同類別之肋決定三種主要的面，據以計算肋之寬、高、牆厚與拔模角，再與肋設計標準進行比較，並提供自動判別與設計變更功能。此一特徵優化技術將擴充至管與套筒的處理。在｢整組模具之關聯性孔洞辨識與簡化｣方面，辨識所有模板上相鄰或同軸的孔洞，每一組關聯性孔洞可跨不同CAD模型。整組模具CAD模型僅保留公、母模仁、流道、澆口、水路等與模流分析有關的孔洞，其餘的孔洞則自動簡化。最後，對整組模具進行網格建構，比較實施前後之網格數量與品質，以驗證前述方法之實用性。 ;In mold flow analysis, the need to mesh an entire mold set, including all mold plates, is increased recently as it can yield more realistic data for further analysis. However, it requires much more time to process the entire mold in comparison with that using a simplified mold base, because the pre-processing of CAD models is tedious and time consuming. In addition, the human effort required for the entire process would be increased if repeated work must be performed due to improper CAD design. The purpose of this project is to investigate the optimization of feature parameters and simplification of related holes for injection molds in mold flow analysis. The former can investigate the correctness of feature design on the CAD model, whereas the latter can simplify unnecessary holes on the mold set in mold flow analysis; both can enhance the efficiency of mold flow analysis. For the optimization of feature parameters, the rib data obtained from feature recognition must further be classified and screened to characterize the dominant faces that can be used to determine the width, height, thickness and draft angle of a rib. For those parameters that are not satisfied, a design modification module is then implemented to modify the shape of the rib. The above-mentioned method is modified slightly to handle tube and boss features. For the simplification of related holes for a mold set, adjacent and coaxial holes on different mold plates are recognized and grouped, including those from different CAD models. Holes belonging to the core, cavity, sprue and cooling channels are preserved as they must be modeled in mold flow analysis, whereas the others on the mold set are simplified. Finally, the mold sets before and after the above-mentioned CAD pre-processing are meshed to verify the feasibility of the proposed method.
