How to block/mesh solid and fluid area separately
 

Hi,

I am trying to mesh a 3D pipe flow. I would like to mesh the fluid and solid areas so when I import the mesh in FLUENT, i will be able to choose one as fluid and one as solid. I've tried to create a block for each of the two bodies, but it does not seem to be correct when jeg apply premesh. And if i just make one block for the whole geometry and split it, it will only export the area to FLUENT as one (either solid or fluid).

I have attached my geometry, so you can see what i mean with fluid (blue) and solid (green) area.

Does anyone have a suggestion to how i make the separately blocks and mesh?

Thank you!

The problem is that FLUENT only solves FLUID. Why do you need to do that? For example, if you solve FLUID, you can delete block of SOLID and that region does not have mesh.