HELP: fsi w ANSYS !!!

Michele

Hi everybody, I'm trying to model blood flow in an arterial vessel and i'm facing this through a fsi ansys analisys.

After setting up the fluid and solid environment (they work in their single field approach), as soon as i start the solver i come to this message:

"number of fluid/solid interfaces do not match for FSIN boundary conditons"

I'm trying to get out of it using different approaches with reference to ansys help and tutorials but i can't understand what does it mean with "[...] do not match..."; are the bc too much? or too less? or just wrong placed?

Thanks a lot

Michele