第二講-創(chuàng)建實體模型-2011

1、By Dr Cui Mao , April 2011,2-1,ANSYS 理論與工程應(yīng)用,第二講創(chuàng)建實體模型,By Dr Cui Mao , April 2011,2-2,ANSYS 理論與工程應(yīng)用,一、實體模型與有限元模型,By Dr Cui Mao , April 2011,2-3,ANSYS 理論與工程應(yīng)用,幾乎所有的有限元分析模型都用實體模型建模，還可以在幾何模型邊界上方便地施加載荷.,幾何實體模型并不參與有限元分析!,By Dr Cui Mao , April 2011,2-4,ANSYS 理論與工程應(yīng)用,所有施加在幾何實體邊界上的載荷或約束必須最終傳遞到有限元模型上（節(jié)點或單元上）

2、進行求解.,由幾何模型創(chuàng)建有限元模型的過程叫作網(wǎng)格劃分（meshing).,By Dr Cui Mao , April 2011,2-5,ANSYS 理論與工程應(yīng)用,幾何實體模型,有限元模型,Meshing,By Dr Cui Mao , April 2011,2-6,ANSYS 理論與工程應(yīng)用,ANSYS中圖元的層次關(guān)系,從最低階到最高階，模型圖元的層次關(guān)系為：,關(guān)鍵點（Keypoints）,線（Lines）,面（Areas）,體（Volumes）,By Dr Cui Mao , April 2011,2-7,ANSYS 理論與工程應(yīng)用,提示:,直接建立高階圖元的過程中,程序自動生成對應(yīng)的低

3、階圖元.,如果低階的圖元連在高階圖元上，直接刪除高階圖元的操作不能刪除低階圖元.,By Dr Cui Mao , April 2011,2-8,ANSYS 理論與工程應(yīng)用,二、工作平面,By Dr Cui Mao , April 2011,2-9,ANSYS 理論與工程應(yīng)用,三、布爾操作,By Dr Cui Mao , April 2011,2-10,ANSYS 理論與工程應(yīng)用,布爾操作,指幾何圖元進行組合計算.,ANSYS的布爾操作包括:,add, subtract, intersect, divide, glue, overlap.,不僅適用于簡單的體素中的圖元，也適用于從CAD系統(tǒng)傳入的

4、復(fù)雜幾何模型.,By Dr Cui Mao , April 2011,2-11,ANSYS 理論與工程應(yīng)用,一個方塊與一個空心的球進行求交（intersect）布爾操作的結(jié)果.,By Dr Cui Mao , April 2011,2-12,ANSYS 理論與工程應(yīng)用,1. Intersect (交集）,By Dr Cui Mao , April 2011,2-13,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-14,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-15,ANSYS 理論與工程應(yīng)用,By Dr Cui

5、 Mao , April 2011,2-16,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-17,ANSYS 理論與工程應(yīng)用,2. Add （相加）,By Dr Cui Mao , April 2011,2-18,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-19,ANSYS 理論與工程應(yīng)用,3. Subtract （相減）,By Dr Cui Mao , April 2011,2-20,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-21,ANSYS 理論與工程應(yīng)用,By D

6、r Cui Mao , April 2011,2-22,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-23,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-24,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-25,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-26,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-27,ANSYS 理論與工程應(yīng)用,Subtract by working plane,By

7、 Dr Cui Mao , April 2011,2-28,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-29,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-30,ANSYS 理論與工程應(yīng)用,4. Divede （分開）：,Subtract 用于相同圖元相減.,Divide 用于不同圖元相減，是不同圖元間的Subtract.,By Dr Cui Mao , April 2011,2-31,ANSYS 理論與工程應(yīng)用,5. Glue (Merge) 粘接（融合）,By Dr Cui Mao , April 2011,

8、2-32,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-33,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-34,ANSYS 理論與工程應(yīng)用,6. Overlap （疊加）,By Dr Cui Mao , April 2011,2-35,ANSYS 理論與工程應(yīng)用,A5,By Dr Cui Mao , April 2011,2-36,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-37,ANSYS 理論與工程應(yīng)用,Overlap 操作與Glue功能基本相同，不同的是Overla

9、p操作輸入的圖元具有重疊的區(qū)域。,By Dr Cui Mao , April 2011,2-38,ANSYS 理論與工程應(yīng)用,7. Partition （分割）,By Dr Cui Mao , April 2011,2-39,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-40,ANSYS 理論與工程應(yīng)用,By Dr Cui Mao , April 2011,2-41,ANSYS 理論與工程應(yīng)用,Partition與Overlap的區(qū)別：,前者是Subtract與Overlap的組合，僅保留非搭接部分 。,By Dr Cui Mao , April 201

10、1,2-42,ANSYS 理論與工程應(yīng)用,注意：,在缺省情況下，布爾操作完成后，輸入的圖元被刪除.,被刪除的圖元編號變成“自由”的 (這些自由的編號將附給新創(chuàng)建的圖元，從最小的自由編號開始).,By Dr Cui Mao , April 2011,2-43,ANSYS 理論與工程應(yīng)用,練習(xí)創(chuàng)建不同類型的面體素，使用前面介紹的布爾操作，觀察結(jié)果. 確認打開相應(yīng)的編號顯示，觀察布爾操作前后，圖元編號的變化.,練習(xí) - 布爾操作,By Dr Cui Mao , April 2011,2-44,ANSYS 理論與工程應(yīng)用,練習(xí) - 角支架: 建模,By Dr Cui Mao , April 2011,M5-45,ANSYS 理論與工程應(yīng)用,練習(xí) - 軸承座,By Dr Cui Mao , April 2011,2-46,ANSYS 理論與工程應(yīng)用,除了磁場分析以外，用戶不需要告訴ANSYS使用的是什么單位制. 只需要自己決定使用何種單位制，然后確保所有輸入的值的單位制保持統(tǒng)一 (ANSYS并不轉(zhuǎn)換單位制).,四、ANSYS分析中的單位制,By Dr Cui Mao , Apr