Hi

I am facing a problem to simulate the penetration of a liquid inside a hyperelastic structure. I have used a predefined model of a water balloon based on FSI simulation I found on Comsol's website, but unfortunately, it didn't treat the contact cases. I tried to find a solution on the internet and what I found is not what I exactly I want by creating a tiny gap between the two surfaces.

Note: as I know, this problem needs Form Assembly but it didn't work.

Thank you in advance.