How to model a compression-only support with displacement constraints?

- March 25, 2022 at 12:10 pm
  
  asierog
  Subscriber
  
  Hello, I am trying to do a Modal Analysis of a 500k element model. In the begining the model had some frictionless contact that had to be changed by No-Separation contacts. The model also has fixed supports and compression only supports. I tried to solve the model but it was impossible, so I decided to change the compression only supports for displacement constraints, setting X,Y free and Z=0, but I know they aren´t equal. Does it exist some way to model a compression-only support with displacement constraints, or is it possible to solve the model using compression only support?
  Thank you in advance,
  A.O.G.
- March 25, 2022 at 2:04 pm
  
  John Doyle
  Ansys Employee
  
  The compression only support is simulated using a rigid-flex contact pair under the hood. The contact surface will not penetrate across the rigid target, but is free to separate. It should be in a closed and sliding status. For the modal, it should be reduced to its linear equivalent, which would be no-separation. I think your manually defined displacement constraints do same thing, assuming Z is normal to the compression only surface.
- March 28, 2022 at 7:18 am
  
  asierog
  Subscriber
  
  Thank you very much Regards from Spain