I have created a grid interface at the junction between two 3D pipes (at right angles) in Fluent.

This action did not create any extra interface boundary at the overlap face. Only two ghost walls are created (which dont do anything).

Now when I solve the flow, the flow paths show evidence that the grid interface is preventing the flow into the 2nd volume. There is still flow through this interface, but it is being restricted by the interface between the two volumes.

Why is this interface restricting flow?

How do I solve this problem?

Thanks

Have u defined it as a non-conformal interface? Also define it without switching 'coupled' option.

Yeah I did both of those things. I am thinking that the problem is caused by two meshes on the interfaces being too different. I will modify my mesh and see what effect that has.

Dear Ed:

If the two mesh size are far different it may cause this problem, I recommend to choose the finer mesh as grid interface 1. If you got better results, then try to change the mesh size in two or more steps.

Best Regards

Mehdi Ghoddosi