I am trying to deploy a simple section of a stent geometry using a balloon. I have defined a polar coordinate system for which I displace the balloon in the radial direction. This deforms the stent. The boundary conditions I have set on the stent is to fix the proximal end axially and prevent tangential displacement at the distal end. The remaining struts are also constrained in the tangential direction. The whole body is free to move in the radial direction allowing increase in diameter.

The difficulty I am having is defining the tangential displacement boundary conditions. While it appears to work correctly on the repeating struts, the deformation is not expected on the far end. I have tried various different boundary conditions but all with the same effect. Applying no boundary condition at the distal end causes large contact separation which is not expected in this model. I have tried applying the tangential constraint to a nodal selection, a few nodes only and the whole face.

I have attached an image of the results I get when applying the boundary conditions listed above and constraining the whole distal face in the tangential direction. I will also include the workbench file in a comment to this thread

Any help would be greatly appreciated.

Thanks

J