Modelling Rectangle Plane-Element

- May 14, 2018 at 9:25 am
  
  maetha
  Subscriber
  
  Hey there
  
  I'd like to model a simple plane in the x-y-plane with a thickness of 0.2 m and a bilinear Ansatzfunction. How can I choose which type of element ANSYS is going to use for it's meshing or calculation?
  
  I'm using ANSYS 19 Academic.
  
  Thanks for your help
- May 14, 2018 at 12:43 pm
  
  peteroznewman
  Subscriber
  
  Hey Maetha,
  
  You can tell ANSYS to mesh with linear elements, and not quadratic. I think that is what you want. A rectangular shell element will have a bilinear shape function.
  
  Click on the Mesh title in the outline in Mechanical. In the Defaults portion is Element Order which can be set to Linear.
  
  After you solve, if you let ANSYS automatically select an element for you, you can see what element was used and what Keyops were used by searching through the solver output file.
  
  There are ways to make ANSYS use a different element type or different Keyops, but is this sufficient for now?
  
  I have attached an ANSYS 18.2 archive that you can open in 19.
- May 14, 2018 at 1:36 pm
  
  maetha
  Subscriber
  
  Hey Peter
  
  thanks for your fast response. I tried your idea before.
  
  What I'd like to get is the result of the manual calculation (s. attached file). They just mesh the geometry with a single finite element and are getting a displacement in x-direction of 3.69e-04 m at node 3. If I mesh it with a single element in Ansys I get 0.48mm. I'm not sure where this difference is coming from. Maybe from a different element type?
  
  Thank you!
- May 14, 2018 at 11:24 pm
  
  peteroznewman
  Subscriber
  
  Hey Maetha,
  
  I'm not deep into the theory behind the elements, I'm go deep on the application of the tool.
  
  I meshed with 1 element and got your 0.48 mm result. You are trying to match the value of 0.37 mm that are from some equations. I don't know what those equations are.
  
  If you take that geometry and instead of a 3D shell181 element, you create a 2D plane stress model and use a plane182 element. Then the x-deformation is 7.95 mm!
  
  You best bet is to dive into the ANSYS Help system that has a Theory section and an Element Reference section.
  
  Good luck!
- May 22, 2018 at 8:19 am
  
  maetha
  Subscriber
  
  Hey Peter
  
  I will do that. Thank you!
- May 23, 2018 at 12:20 pm
  
  maetha
  Subscriber
  
  I now changed the elementtype to SHELL63 which is leading me to manual computed results.
  
  Thanks for your help!