Ansys Submodeling

1. Course in ANSYS
Example0702
Example – Plate with a hole
A
Objective: E = 210000N/mm2
Determine the maximum stress in the x-direction for n = 0.3
point A and display the deformation figure
Tasks: a = 200mm
Create a submodel to increase the accuracy of the FEA b = 100mm
without increasing the computational effort significantly? t = 10mm
Topics: r = 10mm
2
Element type, Real constants, modeling, mapped mesh, s = 100N/mm
plot results, output graphics, path operations,
submodeling
Example0702 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.
Example0702 3
Example - title
Utility Menu > File > Change Jobname GUI
/jobname, Example0702_coarse Command line entry
Enter: Example0702_coarse
Utility Menu > File > Change Title Enter: Plate with a hole
/title, Plate with a hole
Example0702 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
Enter 0 or Enter 50
Press OK leave empty
Note: Keypoints (4 kp’s) and lines
(4 lines) are automatically generated
(also numbered automatically)
Example0702 5
Example – Areas Rectangle
Example0702 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)
Example0702 7
Example - Area
Example0702 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
Example0702 9
Example – Areas
Example0702 10
5

6. Example - Numbering
Switch on Keypoint, Line, and Area Numbers
Example0702 11
Example - List Menu
List Keypoint, Lines, and Areas
Example0702 12
6

7. Example - Plot Menu
Plot Keypoint, Lines, and Areas
Example0702 13
Example – Element Type
Preprocessor > Element Type > Add/Edit/Delete
Press Add
Example0702 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.
Example0702 15
Example – Real Constants
Preprocessor > Real Constants > Add
Place the cursor
on the relevant
element and
press OK
Example0702 16
8

9. Example - Real Constants
Preprocessor > Real Constants > Add
Enter 10
Press Close
to finish
Press OK
Example0702 17
Example - Material Properties
Preprocessor > Material Props > Material Models
Double Click
to step in the
material tree
Example0702 18
9

10. Example - Material Properties
Preprocessor > Material Props > Material Models
Enter 210000 Click here
Modulus of elasticity to Close
Enter 0.3
Poisson’s ratio
Press OK
Example0702 19
Example - Meshing
Preprocessor > Meshing > Size Cntrls > ManualSize > Lines > Picked Lines
Select/Pick
Lines to
specify See next page
mesh size
for
Pick the two
longest lines
Press OK when finish with selection
Example0702 20
10

11. Example – Mesh Size
3 Element subdivisions
6 Element subdivisions
5 Element subdivisions
Example0702 21
Example – Concatenate Lines
Select L2 and L3 to create
a topologically four sided
Press OK geometry
Example0702 22
11

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
Example0702 23
Example – Mapped Mesh
Example0702 24
12

13. Example – Analysis Type
File > Write DB log file
Enter “example0702_coarse.lgw”
Solution > Analysis Type > New Analysis
Example0702 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
Example0702 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
Example0702 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 Example0702 28
14

15. Example - Save
Display of Analysis model
Save the model
Example0702 29
Example - Solve
Solution > Solve > Current LS
Press OK
Example0702 30
15

16. Example - Solve
Press Close
Press here
to Close
Example0702 31
Example – Contour Plot
General Postproc > Plot Results > Contour Plot > Nodal Sol
Select Stress
Select SX for stresses in
x-direction
Example0702 32
16

17. Example – Contour Plot
Example0702 33
Example – Select - Entities
See next page
for selection
Example0702 34
17

18. Example – Select Nodes
Select the
indicated
nodes
Enter OK when finished Example0702 35
Example – List Results
Select Stress, SCOMP
Press OK
Example0702 36
18

19. Example – List Results
Example0702 37
Example - Plot - Nodes
Plot Nodes
Only 11 FE nodes are
displayed – the same nodes as
selected previously
Example0702 38
19

20. Example – Select - Entities
Select Pick All
Example0702 39
Example - Plot - Nodes
Plot Nodes
Example0702 40
20

21. Example - Plot - Nodes
Example0702 41
Example – Define Path
See next page for selection
Example0702 42
21

22. Example – Define Path - By Nodes
Select the
indicated
nodes
Note: the
selection
order is
important –
start from the
hole
Enter OK when finished Example0702 43
Example – Define Path - By Nodes
Enter an appropiate name, e.g. SSX
Enter OK
Example0702 44
22

23. Example – Map onto Path
Select Stress, SX
Press OK
Example0702 45
Example – Plot Path on Graph
Select SX
Press OK
Example0702 46
23

24. Example – Plot Path on Graph
Example0702 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.
Example0702 48
24

25. Example - title
Utility Menu > File > Change Jobname GUI
/jobname, Example0702_fine Command line entry
Enter: Example0702_fine
Utility Menu > File > Change Title Enter: Plate with a hole
/title, Plate with a hole
Example0702 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
Enter 0 or Enter 25
Press OK leave empty
Note: Keypoints (4 kp’s) and lines
(4 lines) are automatically generated
(also numbered automatically)
Example0702 50
25

26. Example – Areas Rectangle
Example0702 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)
Example0702 52
26

27. Example - Area
Example0702 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
Example0702 54
27

28. Example – Areas
Example0702 55
Example - Numbering
Switch on Keypoint, Line, and Area Numbers
Example0702 56
28

29. Example - List Menu
List Keypoint, Lines, and Areas
Example0702 57
Example - Plot Menu
Plot Keypoint, Lines, and Areas
Example0702 58
29

30. Example – Element Type
Preprocessor > Element Type > Add/Edit/Delete
Press Add
Example0702 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.
Example0702 60
30

31. Example – Real Constants
Preprocessor > Real Constants > Add
Place the cursor
on the relevant
element and
press OK
Example0702 61
Example - Real Constants
Preprocessor > Real Constants > Add
Enter 10
Press Close
to finish
Press OK
Example0702 62
31

32. Example - Material Properties
Preprocessor > Material Props > Material Models
Double Click
to step in the
material tree
Example0702 63
Example - Material Properties
Preprocessor > Material Props > Material Models
Enter: Click here
Modulus of elasticity to Close
Enter:
Poisson’s ratio
Press OK
Example0702 64
32

33. Example - Meshing
Preprocessor > Meshing > Size Cntrls > ManualSize > Lines > Picked Lines
Select/Pick
Lines to
specify See next page
mesh size
for
Pick the two
longest lines
Press OK when finish with selection
Example0702 65
Example – Mesh Size
6 Element subdivisions
12 Element subdivisions
10 Element subdivisions
Example0702 66
33

34. Example – Concatenate Lines
Select L2 and L3 to create
a topologically four sided
Press OK geometry
Example0702 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
Example0702 68
34

35. Example – Mapped Mesh
Example0702 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
Example0702 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
Example0702 71
Example - Submodel
Example0702 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.
Example0702 73
Example – CBI Steps
• The following tasks are involved in
performing the cut boundary
interpolation:
1. Identify and write the cut-boundary nodes
cut-
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
Example0702
file
37

38. Example – CBI: Step 1
Plot Nodes
Example0702 75
Example – CBI: Step 1
See next page
for selection
Example0702 76
38

39. Example – CBI: Step 1
Example0702 77
Example – CBI: Step 1
Plot Nodes
Example0702 78
39

40. Example – CBI: Step 1
Example0702 79
Example – CBI: Step 1
Press OK Enter example0702_cutboundary
Example0702 80
40

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
Example0702 81
Example – CBI: Step 2
Select Pick All
Example0702 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
Example0702 83
Example – CBI: Step 3
Enter example0702_coarse.db
Press OK
Example0702 84
42

43. Example – CBI: Step 3
Example0702 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
Example0702 86
43

44. Example – CBI: Step 4-6
Select All items
Browse to find the result file
see next page
Example0702 87
Example – CBI: Step 4-6
Read the First Set
Enter example0702_coarse.rst
Example0702 88
44

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 cut-boundary interpolation
cut-
8. All interpolation work is now done
Example0702 89
Example – CBI: Step 7
Press OK Browse to find
example0702_cutboundary
Example0702 90
45

46. Example – CBI: Step 7
Enter example0702_fine.db Press OK
Example0702 91
Example – CBI: Step 7
Load the example0702_fine.cbdo
Press OK
Example0702 92
46

47. Example – CBI: Step 8
Example0702 93
Example - Solve
Press Close
Press here
to Close
Example0702 94
47

48. Example – Contour Plot
General Postproc > Plot Results > Contour Plot > Nodal Sol
Select Stress
Select SX for stresses in
x-direction
Example0702 95
Example – Contour Plot
Example0702 96
48

49. Example – Select - Entities
See next page
for selection
Example0702 97
Example – Select Nodes
Select the
indicated
nodes
Enter OK when finished Example0702 98
49

50. Example – List Results
Select Stress, SCOMP
Press OK
Example0702 99
Example – List Results
Example0702 100
50

51. Example - Plot - Nodes
Plot Nodes
Only 21 FE nodes are
displayed – the same nodes as
selected previously
Example0702 101
Example – Select - Entities
Select Pick All
Example0702 102
51

52. Example - Plot - Nodes
Plot Nodes
Example0702 103
Example - Plot - Nodes
Example0702 104
52

53. Example – Define Path
See next page for selection
Example0702 105
Example – Define Path - By Nodes
Select the
indicated
nodes
Note: the
selection
order is
important –
start from the
hole
Enter OK when finished Example0702 106
53

54. Example – Define Path - By Nodes
Enter an appropiate name, e.g. SSX
Enter OK
Example0702 107
Example – Map onto Path
Select Stress, SX
Press OK
Example0702 108
54

55. Example – Plot Path on Graph
Select SX
Press OK
Example0702 109
Example – Plot Path on Graph
Example0702 110
55

56. File menu
You can include commands to be
executed when the program starts up in
the start71.ans file.
Clears (zeros out) the database stored in
memory. Clearing the database has the same
effect as leaving and reentering the ANSYS
program, but does not require you to exit.
Example0702 111
56