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研究生: 王齊
Qi Wang
論文名稱: 四邊形網格自動建構之多尺寸輪廓撒點技術研究
指導教授: 賴景義
Jiing-Yih Lai
口試委員:
學位類別: 碩士
Master
系所名稱: 工學院 - 機械工程學系
Department of Mechanical Engineering
論文出版年: 2024
畢業學年度: 112
語文別: 中文
論文頁數: 128
中文關鍵詞: 輪廓撒點多尺寸撒點四邊形網格網格建構模流分析
外文關鍵詞: contour seeding, multi-size seeding, quadrilateral mesh, mesh generation, mold flow analysis
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  • 塑膠射出成型製程中,需要開發製造成本高昂的模具。目前為了降低模具的製造成本,通常會先進行模流分析,以模擬使用者的設計。透過此方式,可以確保設計符合產品的需求,然後再開始製造模具,從而達到節省成本的目標。模流分析是透過實體網格,模擬射出成型的過程與結果,因此設計階段的CAD模型,需要轉換成實體網格,才能夠執行模流分析。如果實體網格數量過多,模流分析的計算時間將會過長。實體網格是由表面網格轉換而成,而表面網格的建構過程中,需要先進行輪廓撒點,才能夠建構表面網格。表面網格建構中,第一層的網格大小,是依照輪廓撒點間距的尺寸,也會間接影響整個CAD模型的網格尺寸,因此輪廓撒點與網格尺寸相關。本研究開發多尺寸輪廓撒點方法,使得網格建構的尺寸能夠變化。具體來說,對於簡單的輪廓,使用大尺寸的網格;對於複雜微小的輪廓,則使用小尺寸的網格。這樣可以減少CAD模型的網格數量,從而縮短模流分析計算的時間。本研究的多尺寸撒點方法,特別適合應用於IC CAD的模流分析。經過多個範例測試,本研究的多尺寸撒點相較於傳統的單一尺寸撒點,能夠將模流分析時間減少50.40%至99.11%。故本研究的撒點技術,可顯著地改善模流分析的計算效率。


    n plastic injection molding processes, developing molds can incur high manufacturing costs. To reduce these costs, mold flow analysis is typically conducted upfront to simulate user designs. This ensures designs meet product requirements before mold production begins, achieving cost savings goals. Mold flow analysis simulates the injection molding process and its outcomes using physical meshes. Therefore, CAD models at the design stage need to be converted into physical meshes for this analysis. Excessive mesh complexity can lead to prolonged computation times during mold flow analysis. Surface meshes are derived from contour seedings during their construction process. The size of the initial mesh layer is dictated by the spacing of these contour seedings, indirectly affecting the overall CAD model mesh size. This research introduces a multi-size contour seeding method to vary mesh construction dimensions. Specifically, larger meshes are used for simpler contours, while smaller meshes are applied to intricate, small-scale contours. This approach reduces the number of CAD model meshes, thereby shortening mold flow analysis computation times. Particularly suited for IC CAD mold flow analysis, this multi-size seeding method significantly outperforms traditional single-size seeding, reducing analysis times by 50.40% to 99.11% across multiple test cases. Hence, this seeding technique markedly enhances the computational efficiency of mold flow analysis.

    摘要......i Abstract......ii 致謝......iii 目錄......iv 圖目錄......vii 表目錄......xi 第一章 緒論......1 1.1 前言......1 1.2 文獻回顧......2 1.3 研究目的......3 1.4 研究方法......5 1.5 論文架構......5 第二章 輪廓撒點方法回顧及問題分析......8 2.1 前言......8 2.2 輪廓撒點整體流程......8 2.3 輪廓撒點方法細部說明......10 2.3.1 輸入2D形狀輪廓......10 2.3.2 輪廓及邊資料建立......11 2.3.3 邊長及曲線分類......11 2.3.4 邊的參數方向排序......15 2.3.5 均勻與非均勻輪廓節點建構......17 2.3.6 輪廓節點資料建立......17 2.4 輪廓撒點方法回顧......17 2.4.1 均勻輪廓撒點......17 2.4.2 非均勻輪廓撒點......19 2.5 問題分析......23 2.5.1 案例分析......23 2.5.2 改善目標......30 第三章 多尺寸輪廓撒點之演算法......34 3.1 前言 ......34 3.2 多尺寸輪廓撒點方法概述......34 3.3 多尺寸撒點流程......38 3.4 內外輪廓撒點間距不同......48 3.4.1 雙尺寸應用於均勻撒點......51 3.4.2 三尺寸應用於均勻撒點......51 3.5 線性變化輪廓撒點間距......59 3.6 整合非均勻撒點技術......61 第四章 多尺寸輪廓撒點之結果分析......68 4.1 前言......68 4.2 撒點技術之表面網格建構影響......68 4.2.1 單一尺寸......76 4.2.2 雙尺寸......80 4.2.3 三尺寸......87 4.2.4 線性變化輪廓撒點間距......90 4.2.5 整合多種撒點技術與非均勻撒點......97 4.3 多種撒點技術之模流分析影響......103 第五章 結論與未來展望......108 5.1 結論 ......108 5.2 未來展望......109 參考文獻......111

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