Multi Layer Cylinder Shell

- February 15, 2022 at 4:46 pm
  
  francescocurzio
  Subscriber
  
  Hi everyone, new LS DYNA user here! I have an issue in the creation on of a multi layer concentrical shell cylinder! Which is the best way to createa model of this type? Now i created the different layers of the model using shape mesher and the cylinder shell option, so every time i have putted the value of the radius of each layer, but in this the way (due to a coarse mesh) in some points i have compenetrations of layers. How can i resolve this one?
  Thanks!
- February 16, 2022 at 9:34 pm
  
  Andreas Koutras
  Ansys Employee
  
  I think I understand the issue. If the mesh is too coarse you cannot avoid these penetrations. In LS-PrePost, you can have the shell thickness displayed by going to: Model and Part -> Appearance -> Thick -> ShellThickness. If you are planning to use contacts between the layers , try with IGNORE=1 or 2 in optional card c of *CONTACT. See the manual for the definition of IGNORE.
  Alternatively, you can use thick shells (tshell) instead of thin shells.
  I hope this helps.
- February 17, 2022 at 5:55 pm
  
  francescocurzio
  Subscriber
  
  thank you so much, i resolved the problem using the same number of elements in the circumfernetial direction for each components. Probably this will lead me to have a coarse mesh in the outer layers, but i cant use an extremely fine mesh in the inner layers due the elevated number of elements in the model.