Inflation of angioplasty balloon

[jamescook]

Hi I'm trying to model the inflation of a simple model of an angioplasty balloon consisting of a straight cylinder with tapered ends to about 4 times the original diameter of the cylinder however I cannot get many of my models to converge and for any that do converge the resulting increase in diameter is minimal. At present I am more concerned with achieving the required deformation for the given geometry than with using accurate material properties. I am currently using Standard but would Explicit be more appropriate? I am inflating the balloon using a pressure load and have constrained all displacements at its ends. Any input you may have would be appreciated. The input file is attached.

 

[rstupplebeen]

1. BC-1 which constrains U2 has some extra nodes compared to the other BCs.
2. How accurate is a fixed constraint at the top and bottom? That is as if it were glued to 2 steel plates. (I think this is the main issue)
3. Can this be an axi-symmetric model?
I hope this helps.



Rob Stupplebeen

 

[jamescook]

Thanks for your advice I am trying using different bcs. Is there anything I could do with the material model to increase the deformation of the balloon

 

[rstupplebeen]

You could model it as a hyperelastic material. Attached is a good approximation from a modulus if you do not have test data. I hope this helps.

Rob Stupplebeen