Mesh Interface in Fluent
 

Hello guys,

I have the following challenge.
I am considering a duct flow and I divided the duct into two parts in order to apply a structured mesh to the simpler part and an unstructured to the more complex geometry.
I am using Ansys meshing and Fluent.
For me this challenge seems easy but the Interface does not work even if it is just a virtual one.
Can someone simply describe how he would attack this issue and specify the Interface?

Many thanks in advance.