strong deformation of shell elements in mfx
 

Dear experts!

I'm trying to simulate bridge flutter using mfx. I have a cfx model and a 3d ansys model using shell elements. My problem is that the shell elements deform rudely during the first few multifield time steps. The reason could be that the shell elements are unloaded at the initial time step and over only one time step they get a sudden load.

Can anybody propose a solution for my problem???

Thanks Geri