Ansys

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There are multiple ways to generate geometry in Ansys.
There are multiple ways to generate geometry in Ansys.
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[[Image:Ansys1.PNG|center]]
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[[Image:Ansys1.PNG]]
Figure 1. Angle Bracket
Figure 1. Angle Bracket
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[[Image:Ansys2.PNG|center|Figure 2 Created two rectangles.]]
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[[Image:Ansys3.PNG]]
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Figure 2. Created two rectangles  
Figure 2. Created two rectangles  
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      2. [[[Image:1_2.JPG]]]
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[[Image:Ansys2.PNG]]
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Figure 3. Rounded corners  
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            Figure 3. Rounded corners  
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      3. [[[Image:1_3.bmp]]]
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            Figure 4. Filleted with lines
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      4. [[[Image:1_4.bmp]]]
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            Figure 5. Filleted with lines
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      5. [[[Image:1_5.bmp]]]
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            Figure 6. Subtracted area of hole
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Method 2
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      1. [[[Image:2_1.bmp]]]
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            Figure 7. Created arcs
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      2. [[[Image:2_2.bmp]]]
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            Figure 8. Created arcs
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      3. [[[Image:2_3.bmp]]]
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            Figure 9. Created lines
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      4. [[[Image:2_4.bmp]]]
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[[Image:Ansys4.PNG]]
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            Figure 10. Created area
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Figure 4. Filleted with lines
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      5. [[[Image:2_5.bmp]]]
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[[Image:Ansys5.PNG]]
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            Figure 11. Subtracted area of hole
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Figure 5. Filleted with lines
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Modelling Path
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[[Image:Ansys6.PNG]]
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[[[Image:modellingpath.JPG]]]
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Figure 6. Subtracted area of hole
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Figure 12.
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'''Method 2'''
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Meshing
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[[[Image:meshing.JPG]]] 2/15 used an element mesh size of .25 while 13/15 used an element mesh size of .5. Figure 13.
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[[Image:Ansys7.PNG]]
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Loading
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    *
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Figure 7. Created arcs
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      6/15 users accounted for depth and applied 80 psi
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[[Image:Ansys8.PNG]]
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    *
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Figure 8. Created arcs
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      8/15 used 10 psi from the diagram
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[[Image:Ansys9.PNG]]
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    *
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      1/15 did not use either
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Figure 9. Created lines
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      All users applied 0 displacement
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[[Image:Ansys10.PNG]]
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Results
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Figure 10. Created area
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[[[Image:meshingerror.JPG]]]
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[[Image:Ansys11.PNG]]]
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    *
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Figure 11. Subtracted area of hole
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      With constant pressure, average difference due to modelling is 19.94%
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'''Modelling Path'''
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    *
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      WIth constant pressure and constant mesh size, average difference is 23%
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[[Image:Ansys12.PNG]]
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    *
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      Meshing affected the results by 3%
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Figure 12
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[[[Image:pressurediff.JPG]]]
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'''Meshing'''
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    *
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[[Image:Ansys13.PNG]] 2/15 used an element mesh size of .25 while 13/15 used an element mesh size of .5
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      Same model given two different pressures
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Figure 13.
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    *
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      Percent difference due to pressure difference is 87.5%
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'''Loading'''
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Conclusion
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*6/15 users accounted for depth and applied 80 psi
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*8/15 used 10 psi from the diagram
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*1/15 did not use either
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*All users applied 0 displacement
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    *
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'''Results'''
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      The greater the difference in modelling, the greater the difference in Ansys results.
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[[Image:Ansys14.PNG]]
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    *
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      By setting a tighter criterion for convergence, the difference due to meshing should go to zero.
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*With constant pressure, average difference due to modelling is 19.94%
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    *
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*WIth constant pressure and constant mesh size, average difference is 23%
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*Meshing affected the results by 3%
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      The same loading will produce the same results.  
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[[Image:Ansys15.PNG]]
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Links
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*Same model given two different pressures
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*Percent difference due to pressure difference is 87.5%
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    *
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'''Conclusion'''
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      http://en.wikipedia.org/wiki/ANSYS
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*The greater the difference in modelling, the greater the difference in Ansys results.
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    *
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*By setting a tighter criterion for convergence, the difference due to meshing should go to zero.
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*The same loading will produce the same results.
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      http://computing.ee.ethz.ch/sepp/ansys-6.0-bo/structural_tut.html
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'''Links'''
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*http://en.wikipedia.org/wiki/ANSYS
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*http://computing.ee.ethz.ch/sepp/ansys-6.0-bo/structural_tut.html

Current revision

Effect of Modelling on Ansys

Ansys is a finite element analysis software used for numerically solving static/dynamic structural problems, thermal, electromagnetics, acoustics and fluid problems. The results that are obtained reflect how the model was generated, loaded and meshed. When performing a geometry optimization using Ansys, users must take into account all of these factors. By exploring a case study, the sensitivity of Ansys to these changes can be visualized. Modelling

There are multiple ways to generate geometry in Ansys.

Image:Ansys1.PNG

Figure 1. Angle Bracket

Using log files obtained from a CMU undergrad mechanical engineering course, there were two main methods in which users approached this problem.

Method 1


Image:Ansys3.PNG

Figure 2. Created two rectangles

Image:Ansys2.PNG

Figure 3. Rounded corners

Image:Ansys4.PNG

Figure 4. Filleted with lines

Image:Ansys5.PNG

Figure 5. Filleted with lines

Image:Ansys6.PNG

Figure 6. Subtracted area of hole

Method 2

Image:Ansys7.PNG

Figure 7. Created arcs

Image:Ansys8.PNG

Figure 8. Created arcs

Image:Ansys9.PNG

Figure 9. Created lines

Image:Ansys10.PNG

Figure 10. Created area

Image:Ansys11.PNG]

Figure 11. Subtracted area of hole

Modelling Path

Image:Ansys12.PNG

Figure 12

Meshing

Image:Ansys13.PNG 2/15 used an element mesh size of .25 while 13/15 used an element mesh size of .5

Figure 13.

Loading

  • 6/15 users accounted for depth and applied 80 psi
  • 8/15 used 10 psi from the diagram
  • 1/15 did not use either
  • All users applied 0 displacement

Results

Image:Ansys14.PNG

  • With constant pressure, average difference due to modelling is 19.94%
  • WIth constant pressure and constant mesh size, average difference is 23%
  • Meshing affected the results by 3%

Image:Ansys15.PNG

  • Same model given two different pressures
  • Percent difference due to pressure difference is 87.5%

Conclusion

  • The greater the difference in modelling, the greater the difference in Ansys results.
  • By setting a tighter criterion for convergence, the difference due to meshing should go to zero.
  • The same loading will produce the same results.

Links

Retrieved from "https://wiki.ece.cmu.edu/ddl/index.php/Ansys"
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