Is there a reliable way to define a structural load over a FSI?
I'm using Ansys 2019 R3 Academic. In a Static Acoustics module, I am trying to define a pressure over the structural region (i.e. at the FSI) to simulate the effect of atmospheric pressure. I find that sometimes Mechanical allows me to define this pressure without issue, and sometimes it gives me an error stating "This structural load should be defined on bodies belonging to Physics Region which has structural definition set to Yes."
What I think is happening is sometimes Mechanical interprets the shared surface as belonging to the structural region and allows me to define a pressure over it, but sometimes it interprets it as acoustic region and produces this error. Is there a workaround or best practice that can help avoid this problem?
In the below images I have hidden the overlying acoustic region since they obscure the surface of interest.