最新复合材料层合板分析精品课件.ppt

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1、进入夏天，少不了一个热字当头，电扇空调陆续登场，每逢此时，总会进入夏天，少不了一个热字当头，电扇空调陆续登场，每逢此时，总会想起那一把蒲扇。蒲扇，是记忆中的农村，夏季经常用的一件物品。记想起那一把蒲扇。蒲扇，是记忆中的农村，夏季经常用的一件物品。记忆中的故乡，每逢进入夏天，集市上最常见的便是蒲扇、凉席，不论男女老忆中的故乡，每逢进入夏天，集市上最常见的便是蒲扇、凉席，不论男女老少，个个手持一把，忽闪忽闪个不停，嘴里叨叨着少，个个手持一把，忽闪忽闪个不停，嘴里叨叨着“怎么这么热怎么这么热”，于是三，于是三五成群，聚在大树下，或站着，或随即坐在石头上，手持那把扇子，边唠嗑五成群，聚在大树下，或站着

2、，或随即坐在石头上，手持那把扇子，边唠嗑边乘凉。孩子们却在周围跑跑跳跳，热得满头大汗，不时听到边乘凉。孩子们却在周围跑跑跳跳，热得满头大汗，不时听到“强子，别跑强子，别跑了，快来我给你扇扇了，快来我给你扇扇”。孩子们才不听这一套，跑个没完，直到累气喘吁吁，。孩子们才不听这一套，跑个没完，直到累气喘吁吁，这才一跑一踮地围过了，这时母亲总是，好似生气的样子，边扇边训，这才一跑一踮地围过了，这时母亲总是，好似生气的样子，边扇边训，“你你看热的，跑什么？看热的，跑什么？”此时这把蒲扇，是那么凉快，那么的温馨幸福，有母亲此时这把蒲扇，是那么凉快，那么的温馨幸福，有母亲的味道！蒲扇是中国传统工艺品，在我国

3、已有三千年多年的历史。取材的味道！蒲扇是中国传统工艺品，在我国已有三千年多年的历史。取材于棕榈树，制作简单，方便携带，且蒲扇的表面光滑，因而，古人常会在上于棕榈树，制作简单，方便携带，且蒲扇的表面光滑，因而，古人常会在上面作画。古有棕扇、葵扇、蒲扇、蕉扇诸名，实即今日的蒲扇，江浙称之为面作画。古有棕扇、葵扇、蒲扇、蕉扇诸名，实即今日的蒲扇，江浙称之为芭蕉扇。六七十年代，人们最常用的就是这种，似圆非圆，轻巧又便宜的蒲芭蕉扇。六七十年代，人们最常用的就是这种，似圆非圆，轻巧又便宜的蒲扇。蒲扇流传至今，我的记忆中，它跨越了半个世纪，也走过了我们的扇。蒲扇流传至今，我的记忆中，它跨越了半个世纪，也走过

4、了我们的半个人生的轨迹，携带着特有的念想，一年年，一天天，流向长长的时间隧半个人生的轨迹，携带着特有的念想，一年年，一天天，流向长长的时间隧道，袅道，袅WS-2NAS121, Workshop , May 6, 2002nProblem DescriptionuA 1 in. x 1 in. composite plate is loaded with 2000 #/in. in the Y direction on the top edge, 1000 #/in. in both the X direction and Y direction on the right hand side e

5、dge.uThe left side reacts the loads with X, Y, Z, and Ry constraints.WS-3NAS121, Workshop , May 6, 2002WS-4NAS121, Workshop , May 6, 2002WS-5NAS121, Workshop , May 6, 2002WS-6NAS121, Workshop , May 6, 2002WS-7NAS121, Workshop , May 6, 2002WS-8NAS121, Workshop , May 6, 2002WS-9NAS121, Workshop , May

6、6, 2002Step 3. Create a finite element meshIn the Elements menu create surface mesh based on the mesh seeds assigned in the previous steps. a. Select Create / Mesh / Surfaceb. Select Quad as the Elem ShapeClick on surface 1Click ApplyabcdWS-10NAS121, Workshop , May 6, 2002Step 4. Apply boundary cond

7、itions to the modelabcdegfIn Loads/BCsSelect Create / Displacement / NodalFor New Set Name enter “constraints”In Input Data, enter for Translations, for Rotations then OKOn the top menu click on the Curve or Edge iconIn Select Application Region click lefthand edge of the surfaceClick Add and OKa. C

8、lick ApplyWS-11NAS121, Workshop , May 6, 2002Step 5. Apply loads to the model a. On the top menu click Reset Graphicsb. Select Create / Distributed Loads / Element Uniformc. Enter “Dist. Load Y” for New Set Named. In Input Data, Enter for Edge Distr Load , then OKe. In Select Application Region, cli

9、ck on the top curve of the surfacef.Click Add then OKClick ApplybcdegfaWS-12NAS121, Workshop , May 6, 2002Step 5a. Apply loads to the model (cont.) In a similar way create Dist. Load X:a. Enter “Dist. Load X” for New Set Name.b. In Input Data, Enter , then OKc. In Select Application Region, click on

10、 the right hand side curve of the surface, then Add, then OK.Click Applyabc And then create Dist. Load XY:Enter “Dist. Load XY” for New Set Name.In Input Data, Enter , then OKIn Select Application Region, again click on the right hand side curve of the surface, then Add, then OK.Click Applya. Note t

11、hat since the same edge was picked, the loads are combineddeWS-13NAS121, Workshop , May 6, 2002Step 6. Define ply material properties Go to Material menuSelect Create / 2d Orthotropic / Manual InputFor Material Name enter “graphite-epoxy_tape”Click Input Properties, Select Linear Elastic, enter 20e6

12、, 2e6, .35, 1e6, 1e6, 1e6Click OKClick ApplyClick Input Properties again, Select Failure / Stress / Hill and enter 120e3, 13e3, 110e3, 16e3, 13e3, 5000.Click OK a. Click Apply againabcdefghWS-14NAS121, Workshop , May 6, 2002Step 7. Check Element NormalsCheck element normals to determine the location

13、 of ply 1.Select the Element menu:At the top menu click Reset GraphicsAt the top menu click Hide LabelsSelect Verify / Element / Normals Click Draw Normal Vectorsa. Click ApplyabcdeWS-15NAS121, Workshop , May 6, 2002Step 8. Define composite material properties Go to Materials:Select Create/ Composit

14、e/ LaminateAt Material Name enter 8_ply_symmetric_quasiClick tape property name (graphite-epoxy_tape) slowly 8 times to make 8 pliesAt Thickness for all layers enter .0054Click on ply 1s empty Orientation cellEnter the following into the Insert Orientations box: 0 -45 45 90 90 45 -45 0 . Note that t

15、he +-45 degree plies have changed sign due to the element Z axis being in the opposite direction to the global Z axis.Click Load Text Into Spreadsheeta. Click ApplyabcdehfgWS-16NAS121, Workshop , May 6, 2002Step 9. Define a material coordinate system Go to Geometry:Select Create / Coord / 3PointEnte

16、r Coord ID (99 in this case) you want at Coord ID listAt Origin enter 0 0 0At Point on Axis 3 enter 0 0 1At Point on Plane 1-3 enter 0 1 0a. Click ApplyabcdefWS-17NAS121, Workshop , May 6, 2002Step 10. Apply the material coordinate system to the elements Go to Properties:Select Create / 2D / ShellEn

17、ter “composite1” at Property Set NameAt Options select LaminateIn Input Properties click on the composite material name (8_ply_symmetric_quasi)At Material Orientation select CID and then click the material coordinate system 99 on the screenClick OKClick Application Region and click on Surface 1Click

18、 Adda. Click ApplyabdefghcgWS-18NAS121, Workshop , May 6, 2002Step 11. Submit the model to MSC.Nastran for analysis Go to Analysis:Select Analyze / Entire Model / Full RunClick SubcasesAt Available Subcases click DefaultClick Output RequestsAt Form Type select AdvancedAt Output Requests, click twice

19、 STRESS(SORT1,REAL,VONMISES,BINLIN)=ALL;PARAM,NOCOMPS,-1At Composite Plate Opt: select Ply Stresses. Note that PARAM, NOCOMPS,-1 has now changed to 1.Click OKClick Apply at Subcases and then Cancela.And click Apply at the Analyze menuabcefghijdWS-19NAS121, Workshop , May 6, 2002Step 12. Attach xdb R

20、esults File Go to Analysis:Select Attach XDB / Result Entities / LocalClick Select Results FileUse the Select File tool to find your xdb file in your local Patran directory and click it, in this case, “composite1.xdb”Click OKa. Click ApplyabcdeWS-20NAS121, Workshop , May 6, 2002Step 13. Display ply

21、stresses using MSC.PatranTo display the ply 8s 1 direction stresses: go to the Results menu:First turn off the geometry in Plot/Erase Geometry EraseSelect Create / Quick PlotClick Stress TensorClick Position then select Layer 8 and click CloseClick Quantity and select X ComponentClick Displacements

22、Translationala. Click ApplybcdefgaWS-21NAS121, Workshop , May 6, 2002 F A I L U R E I N D I C E S F O R L A Y E R E D C O M P O S I T E E L E M E N T S ( Q U A D 4 ) ELEMENT FAILURE PLY FP=FAILURE INDEX FOR PLY FB=FAILURE INDEX FOR BONDING FAILURE INDEX FOR ELEMENT FLAG ID THEORY ID (DIRECT STRESSES

23、/STRAINS) (INTER-LAMINAR STRESSES) MAX OF FP,FB FOR ALL PLIES 1 HILL 1 6.1711 0.0000 2 7.7170 0.0000 3 6.4169 0.0000 4 7.3154 0.0000 5 7.3154 0.0000 6 6.4169 0.0000 7 7.7170 0.0000 8 6.1711 7.7170 * . Step 14. View ply failure indices in MSC.Nastran To view the failure indices, open the composite1.f

24、06 file in an editor and search for the following section. It is organized as follows:Element numberPly numberPly failure indexPly interlaminar failure indexHighest failure index in elementa. Flag if highest failure index is greater than 1.0 (indicating ply failure)abcdefNote that Patran does not di

25、splay composite failure indices.WS-22NAS121, Workshop , May 6, 2002nHand calculationsuElement 1, ply 2, a 45 degree ply, has the highest failure index of 7.72 but all of the plies have similar values, thus it is difficult to determine which direction to add plies. However, looking at the terms of Hi

26、lls theorem may tell us:uSubstituting values: uShows that the 1 direction is the largest contributor to the failure and thus the composite needs more -45 degree plies. uUsing this same method, it was found that a 20 ply symmetric layup will give failure indices less than 1.0. The layup is a 0 ply, 4

27、 45 plies, 2 45 plies, and 3 90 plies and then a symmetric layup for the other 10 plies.SXYX2212221222221t92. 739. 110. 014. 029. 6313453. 13120378. 4501. 3313378. 43120501. 32222222eeeeeeeeeStep 15. Change layup to make failure indices below 1.0WS-23NAS121, Workshop , May 6, 2002Step 15a. Change la

28、yup to make failure indices below 1.0To change to a new layup: go to Materials:Select Modify / Composite / LaminateIn Laminated Comp. To Modify click 8_ply_symmetric_quasiAt New Material Name enter 0_4x45_2x-45_3x90_symIn the Laminated Composite popup click on ply 1 and then shift click on ply 8 to

29、select all the pliesClick on Delete Selected RowsSelect Text Entry Mode Insert. In the Modify Menu on the right, click slowly on graphite-epoxy_tape 10 times, once for each plyOn Stacking Sequence Convention select SymmetricAt Thickness For All Layers enter .0054Click on the empty ply 1 Orientation

30、cellSelect Text Entry Mode OverwriteIn Overwrite Orientations enter 0 45 45 45 45 -45 -45 90 90 90Click Load Text Into Spreadsheeta.Click ApplyabcdegkjihnmlfWS-24NAS121, Workshop , May 6, 2002Step 16. Analyze the model with the new composite layup Go to Analysis:Select Analyze / Entire Model / Full

31、RunClick Applya. Click Yes on both overwrite messages.abccWS-25NAS121, Workshop , May 6, 2002Step 17. View the changed ply failure indicesTo view the changed failure indices, again open the composite1.f06 file. Note that the failure indices are all below 1.0. F A I L U R E I N D I C E S F O R L A Y

32、E R E D C O M P O S I T E E L E M E N T S ( Q U A D 4 ) ELEMENT FAILURE PLY FP=FAILURE INDEX FOR PLY FB=FAILURE INDEX FOR BONDING FAILURE INDEX FOR ELEMENT FLAG ID THEORY ID (DIRECT STRESSES/STRAINS) (INTER-LAMINAR STRESSES) MAX OF FP,FB FOR ALL PLIES 1 HILL 1 0.6422 0.0000 2 0.7709 0.0000 3 0.7709 0.0000 4 0.7709 0.0000 5 0.7709 0.0000 6 0.6580 0.0000 7 0.6580 0.0000 8 0.7494 0.0000 9 0.7494 0.0000 10 0.7494 0.0000 11 0.7494 0.0000 12 0.7494 0.0000 13 0.7494 0.0000 14 0.6580 0.0000 15 0.6580 0.0000 16 0.7709 0.0000 17 0.7709 0.0000 18 0.7709 0.0000 19 0.7709 0.0000 20 0.6422 0.7709