Example Plate with a hole

Transcription

1 Course in ANSYS Example Plate with a hole A Objective: Determine the maximum stress in the x-direction for point A and display the deformation figure Tasks: Create a submodel to increase the accuracy of the FEA without increasing the computational effort significantly? Topics: Element type, Real constants, modeling, mapped mesh, plot results, output graphics, path operations, submodeling E = N/mm2 n = 0.3 a = 200mm b = 100mm t = 10mm r = 10mm 2 s = 100N/mm 2 1

2 Steps in Submodeling The process for using submodeling is as follows: Create and analyze the coarse model. Create the submodel. Perform cut boundary interpolation (CBI). Analyze the submodel. Verify that the distance between the cut boundaries and the stress concentration is adequate. 3 Example - title Utility Menu > File > Change Jobname /jobname, _coarse GUI Command line entry Enter: _coarse Utility Menu > File > Change Title /title, Plate with a hole Enter: Plate with a hole 4 2

3 Example Areas Rectangle Preprocessor > Modeling > Create > Areas > Rectangle > By Dimensions Create an area given by X=(0,100) and Y=(0,50) Enter 0 or leave empty Enter 100 Press OK Enter 0 or leave empty Enter 50 Note: Keypoints (4 kp s) and lines (4 lines) are automatically generated (also numbered automatically) 5 Example Areas Rectangle 6 3

4 Example Areas Circle Preprocessor > Modeling > Create > Areas > Circle > Solid Circle Create an area given by (X,Y)=(0, 0) and Radius=10 Enter 10 Press OK Note: Keypoints (4 kp s) and lines (4 lines) are automatically generated (also numbered automatically) 7 Example - Area 8 4

5 Example - Operate Preprocessor > Modeling > Operate > Booleans > Subtract > Areas Create the final area by subtracting the circular area from the rectangular area Note: Bottom left corner of ANSYS GUI Select the rectangular area and press OK Note: Bottom left corner of ANSYS GUI Select the circular area Press OK 9 Example Areas 10 5

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7 Example - Plot Menu Plot Keypoint, Lines, and Areas 13 Example Element Type Preprocessor > Element Type > Add/Edit/Delete Press Add 14 7

8 Example - Element Type Preprocessor > Element Type > Add/Edit/Delete Select Plane strs w/thk Press Options Press Help to learn more about the element. 15 Example Real Constants Preprocessor > Real Constants > Add Place the cursor on the relevant element and press OK 16 8

9 Example - Real Constants Preprocessor > Real Constants > Add Enter 10 Press Close to finish Press OK 17 Example - Material Properties Preprocessor > Material Props > Material Models Double Click to step in the material tree 18 9

10 Example - Material Properties Preprocessor > Material Props > Material Models Enter Modulus of elasticity Click here to Close Enter 0.3 Poisson s ratio Press OK 19 Example - Meshing Preprocessor > Meshing > Size Cntrls > ManualSize > Lines > Picked Lines Select/Pick Lines to specify mesh size for See next page Pick the two longest lines Press OK when finish with selection 20 10

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12 Example - Meshing Preprocessor > Meshing > Mesh > Areas > Mapped > 3 or 4 sided Select individual areas to be meshed NB: It is often necessary to Clear the model for example if Element Type or model geometry is to be changed Select all areas defined to be meshed 23 Example Mapped Mesh 24 12

13 Example Analysis Type File > Write DB log file Enter example0702_coarse.lgw Solution > Analysis Type > New Analysis 25 Example Define Loads Solution > Define Loads > Apply > Structural > Displacement > On Lines Select UY to fix the plate in the y-direction Select the bottom straight line Press OK 26 13

14 Example Define Loads Solution > Define Loads > Apply > Structural > Displacement > On Lines Select UX to fix the plate in the x-direction Select the left straight line Press OK 27 Example Define Loads Solution > Define Loads > Apply > Structural > Pressure > On lines Select the right straight line Enter -100 Press OK to finish Note: Pressure acts normal and inward to a surface 28 14

15 Example - Save Display of Analysis model Save the model 29 Example - Solve Solution > Solve > Current LS Press OK 30 15

16 Example - Solve Press Close Press here to Close 31 Example Contour Plot General Postproc > Plot Results > Contour Plot > Nodal Sol Select Stress Select SX for stresses in x-direction 32 16

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24 Example Plot Path on Graph 47 Steps in Submodeling The process for using submodeling is as follows: Create and analyze the coarse model. Create the submodel. Perform cut boundary interpolation (CBI). Analyze the submodel. Verify that the distance between the cut boundaries and the stress concentration is adequate

25 Example - title Utility Menu > File > Change Jobname /jobname, _fine GUI Command line entry Enter: _fine Utility Menu > File > Change Title /title, Plate with a hole Enter: Plate with a hole 49 Example Areas Rectangle Preprocessor > Modeling > Create > Areas > Rectangle > By Dimensions Create an area given by X=(0,25) and Y=(0,25) Enter 0 or leave empty Enter 25 Press OK Enter 0 or leave empty Enter 25 Note: Keypoints (4 kp s) and lines (4 lines) are automatically generated (also numbered automatically) 50 25

26 Example Areas Rectangle 51 Example Areas Circle Preprocessor > Modeling > Create > Areas > Circle > Solid Circle Create an area given by (X,Y)=(0, 0) and Radius=10 Enter 10 Press OK Note: Keypoints (4 kp s) and lines (4 lines) are automatically generated (also numbered automatically) 52 26

27 Example - Area 53 Example - Operate Preprocessor > Modeling > Operate > Booleans > Subtract > Areas Create the final area by subtracting the circular area from the rectangular area Note: Bottom left corner of ANSYS GUI Select the rectangular area and press OK Note: Bottom left corner of ANSYS GUI Select the circular area Press OK 54 27

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30 Example Element Type Preprocessor > Element Type > Add/Edit/Delete Press Add 59 Example - Element Type Preprocessor > Element Type > Add/Edit/Delete Select Plane strs w/thk Press Options Press Help to learn more about the element

31 Example Real Constants Preprocessor > Real Constants > Add Place the cursor on the relevant element and press OK 61 Example - Real Constants Preprocessor > Real Constants > Add Enter 10 Press Close to finish Press OK 62 31

32 Example - Material Properties Preprocessor > Material Props > Material Models Double Click to step in the material tree 63 Example - Material Properties Preprocessor > Material Props > Material Models Enter: Modulus of elasticity Click here to Close Enter: Poisson s ratio Press OK 64 32

33 Example - Meshing Preprocessor > Meshing > Size Cntrls > ManualSize > Lines > Picked Lines Select/Pick Lines to specify mesh size for See next page Pick the two longest lines Press OK when finish with selection 65 Example Mesh Size 6 Element subdivisions 12 Element subdivisions 10 Element subdivisions 66 33

34 Example Concatenate Lines Press OK Select L2 and L3 to create a topologically four sided geometry 67 Example - Meshing Preprocessor > Meshing > Mesh > Areas > Mapped > 3 or 4 sided Select individual areas to be meshed NB: It is often necessary to Clear the model for example if Element Type or model geometry is to be changed Select all areas defined to be meshed 68 34

35 Example Mapped Mesh 69 Example Define Loads Solution > Define Loads > Apply > Structural > Displacement > On Lines Select UY to fix the plate in the y-direction Select the bottom straight line Press OK 70 35

36 Example Define Loads Solution > Define Loads > Apply > Structural > Displacement > On Lines Select UX to fix the plate in the x-direction Select the left straight line Press OK 71 Example - Submodel 72 36

37 Example - Steps in Submodeling The process for using submodeling is as follows: Create and analyze the coarse model. Create the submodel. Perform Cut Boundary Interpolation (CBI). Analyze the submodel. Verify that the distance between the cut boundaries and the stress concentration is adequate. 73 Example CBI Steps The following tasks are involved in performing the cut boundary interpolation: 1. Identify and write the cutcut-boundary nodes 2. Restore the full set of nodes, write the database to Jobname.DB 3. To do the cut boundary interpolation restore the coarse model 4. Enter POST1 5. Point to the coarse results file 6. Read in the desired set of data from the results 74 file 37

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41 Example - CBI Steps The following tasks are involved in performing the cut boundary interpolation: 1. Identify and write the cut-boundary nodes 2. Restore the full set of nodes, write the database to Jobname.DB 3. To do the cut boundary interpolation restore the coarse model 4. Enter POST1 5. Point to the coarse results file 6. Read in the desired set of data from the results file 7. Initiate cut-boundary interpolation 8. All interpolation work is now done 81 Example CBI: Step 2 Select Pick All 82 41

42 Example - CBI Steps The following tasks are involved in performing the cut boundary interpolation: 1. Identify and write the cut-boundary nodes 2. Restore the full set of nodes, write the database to Jobname.DB 3. To do the cut boundary interpolation restore the coarse model 4. Enter POST1 5. Point to the coarse results file 6. Read in the desired set of data from the results file 7. Initiate cut-boundary interpolation 8. All interpolation work is now done 83 Example CBI: Step 3 Enter example0702_coarse.db Press OK 84 42

43 Example CBI: Step 3 85 Example - CBI Steps The following tasks are involved in performing the cut boundary interpolation: 1. Identify and write the cut-boundary nodes 2. Restore the full set of nodes, write the database to Jobname.DB 3. To do the cut boundary interpolation restore the coarse model 4. Enter POST1 5. Point to the coarse results file 6. Read in the desired set of data from the results file 7. Initiate cut-boundary interpolation 8. All interpolation work is now done 86 43

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45 Example - CBI Steps The following tasks are involved in performing the cut boundary interpolation: 1. Identify and write the cut-boundary nodes 2. Restore the full set of nodes, write the database to Jobname.DB 3. To do the cut boundary interpolation restore the coarse model 4. Enter POST1 5. Point to the coarse results file 6. Read in the desired set of data from the results file 7. Initiate cutcut-boundary interpolation 8. All interpolation work is now done 89 Example CBI: Step 7 Press OK Browse to find example0702_cutboundary 90 45

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48 Example Contour Plot General Postproc > Plot Results > Contour Plot > Nodal Sol Select Stress Select SX for stresses in x-direction 95 Example Contour Plot 96 48

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