Twisting a rubber cylinder

[Cryo1]

We have a cylinder made of a hard rubber compound. We will be twisting it on the OD of the cylinder wall while the ID of the cylinder is fixed. How do I apply a uniform twisting force on the surface of the cylinder? I can section it and apply force at intervels along the surface OD. Is there a better way?

 

[GBor]

What are you trying to do, Cryo1? Is there some need to model the entire cylinder? It sounds as though you could model a small piece and get the same results without all the effort of modeling the entire cylinder. My first thought is a 2-D plain strain cross section. Fix the inner edge by changing the surface designation and apply a surface boundary conditions to fix the nodes. You could then tie the outer surface to a single node at the center and apply a torque (moment) at that node.

This may still be the "easy" way to model it. If you need the entire cylinder, you could then "copy: join all copies" to extrude the cylinder. Is the rubber compound homogeneous? Non-linear (I'm assuing this one)?

These are my quick thoughts...

Garland

Garland E. Borowski, PE