Help on the Use of stitchMesh
 

Hello everyone,
I would like to merge two meshes I built separately with gsmh, on a surface in my geometry that I named 'interface' (the same name) for both the parts.
I am not that familiar with the corresponding utilities in OpenFoam (I was wondering to use stitchMesh, rather than MergeMesh in order to get a unique full geometry where the 'interface' patch will result to be internal), so please, is there anyone that could drive me step by step (with the command lines, I mean) for doing that, from the starting point with converting the two separate meshes obtained with gmsh?