Hi,
I am using SHELL181 elements which interact with FLUID30 to generate the
acoustic wave. The results that I am getting is not satisfactory.
When I put the same plate with fully coupled analysis it gives
displacement of .09 MIcron due to an externally applied static pressure.
But when I put this plate alone it gives just .039 which is correct as it
matches with analytical solution for plate. How it is possible? One error
message that coefficient ratio exceeds 1e8 comes, what may be the meaning
of that?
One more error error message is that Real constant set 1 is referred by at
least element type 1 or 4.  Where set one is real constant for element
type 1 that is shell element. How the element type 4 comes in the picture
that is FLUID30 with ux, uy uz.
Please help me to encounter the problem?

Regards

Ashwani Kumar Garg