LS Dyna FSI ICFD pressure oscillation
 

Hi community!

I am using LS Dyna for a FSI simulation. My simulation terminated as the result of an ICFD mesh error. The result comfirmed the large deflection in geometry was attributed to a sudden yet unreasonable oscillation in my fluid pressure (a sudden overshoot).

The problem is not associated with the time step. The time increment is ~ 5E-5, so I am not worrying about this. The velocity inlet - pressure outlet boundary conditions might be the culprit, but I am not sure.

Are there any techniques (or, tricks) I can deploy to stablise the pressure in simulation? Or, alternatively, do you have any other suspects that I should be careful about?

Thank you.