Restrict nodes in a face to the same deformation in 1 direction

- October 14, 2022 at 7:05 am
  
  gherreros
  Subscriber
  
  In an static structural analysis, I have a hollow cylinder with one fixed support applied to one on the basis. I have applied a force perpendicular to the other basis (+z direction). I need to impose a condition so that the z-deformation results in all the nodes on that face are the same, without restricting the deformation in the x and y direction (The value of z-deformation is not known in advance, thats the result I want). Is there a way to do this? An specific APDL command?
  Any help would be appreciated !
- October 14, 2022 at 8:12 am
  
  ErKo
  Ansys Employee
  
  Under COnditions in mechanical choose a coupling and scope it to the face and choose the dof (say Z) to couple to all these nodes in that direction.
  For more info on coupling see the ansys help manual.
  Erik
- October 14, 2022 at 11:56 am
  
  peteroznewman
  Subscriber
  
  Erik’s advice is the way to accomplish exactly what you want, but using coupling is sometimes confusing.
  An approximate method to achieve what you want is to use a Remote Displacement (Behavior = Deformable) on the face, and set Rotation about X and Y to be 0, but leave the Displacement in X, Y and Z Free. This will make the nodes stay on average in the same Z plane. If you use a Constraint Equation, then the nodes will stay exacly in the same Z plane.
  Below is a force applied to the top of the small area without a Remote Displacement.
  Below is the displacement with the Remote Displacement.