[DanieleDeRossi]

Problem with Ansys fluent.
I am trying to replicate something like this paper where they drive a flow through a cubic lattice cell.
https://www.sciencedirect.com/scienc...42727X03001103

I first tried an empty cube with periodic boundary conditions on every side perpendicular to the flow.
I've imposed periodic boundary conditions and was successful.

I'm trying it with a spherical particle inside of the cube. It won't let me impose periodic boundary conditions on the faces.
I thought it may be my mesh.
I tried to impose match control when generating the mesh , but it keeps giving me topology errors. What's wrong?

Other questions-
Can I get similar results with symmetry boundary conditions?