[Techies]

Hi guys,
I'm trying to simulate the NACA airfoil with FSI 2 ways.
But I have a problem
When I increase velocity inlet from 30ms to 35ms to find the limit of velocity causing flutter, the system goes to errors.
They said that : have threw an exception or negative cell volume.
I think because of the deformation, mesh becomes so bad and the system can't handle it.
So how to modify the dynamic mesh to avoid this error or anyone has a experience to handle this case. Please let me know.
Thanks all.
I'm looking forward to hearing from u.