模流分析能夠讓塑膠件產品的設計者，在設計階段確認產品實際製造時可能產生的問題。在進行模流分析前，須將產品的CAD模型轉化為實體網格資料，提供給分析軟體進行計算，而實體網格的數量及品質會分別影響模擬分析的計算時間及分析準確度。若需要較快的分析時間與準確的分析結果，需要搭建六面體網格，但當前六面體網格需要以手動的方式，將模型進行切割，再進行六面體網格的搭建。為了提升六面體網格建構的效率及準確度，本實驗室開發CAD模型體積分解技術，將模型分解為數個形狀較為簡單的區塊，並將區塊以程式自動化的方式建構出網格資料。本研究為針對先前開發的體積分解演算法不足的部分，進行優化及改進，以提高模型分解的完整性，最後結合自動化四邊形網格建構技術，以達到快速將CAD模型轉化為網格的效率。首先，為了分解相連外部凸起特徵之薄殼本體及修正由盲孔特徵導致的錯誤區塊輪廓，會對分解演算法進行修改。最後，為了確保網格建構後不會出現網格交錯的狀況，須建立不同區塊的對應性，藉以提供完整的區塊資料給予自動化網格建構。本研究會與文獻[13]進行比較，在相同的24個案例下，建構的區塊數量會提升180個，並且成功率由95.0%提高至99.3%，有效的減少區塊建構失敗數量。

Mold flow analysis allows designers of plastic parts to confirm possible problems during the actual manufacturing of the product during the design stage. Before performing mold flow analysis, the CAD model of the product must be converted into solid grid data and provided to the analysis software for calculation. The quantity and quality of the solid grid will respectively affect the calculation time and analysis accuracy of the simulation analysis. If you need faster analysis time and accurate analysis results, you need to build a hexahedral grid, but the current hexahedral grid needs to cut the model manually, and then build the hexahedral grid. In order to improve the efficiency and accuracy of hexahedral grid construction, the laboratory has developed CAD model volume decomposition technology, which decomposes the model into several blocks with relatively simple shapes, and constructs grid data from the blocks in a programmatically automated manner . This research is to optimize and improve the insufficient part of the previously developed volume decomposition algorithm to improve the integrity of the model decomposition, and finally combine the automatic quadrilateral mesh construction technology to achieve the efficiency of quickly converting the CAD model into a mesh. First, the decomposition algorithm is modified in order to decompose the shell body connected to the external raised features and to correct the wrong block outline caused by the blind hole feature. Finally, in order to ensure that grid interlacing does not occur after grid construction, the correspondence between different blocks must be established to provide complete block data for automatic grid construction. This study will be compared with literature [13]. Under the same 24 cases, the number of constructed blocks will increase by 180, and the success rate will increase from 95.0% to 99.3%, effectively reducing the number of block construction failures.

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