I use system coupling option when there is heat transfer between two walls or wall and fluid and generally it was available when I was doing 3D simulation. When I use share topology option in Design Modeler case, some faces are missing. When I use share topology option with SpaceClaim , system coupling and thermal coupling option are showing but still I can't get cell zone condition which I have assigned. I have meshed geometry in ANSYS meshing and I created necessary Named Selection there. In 'Check Geometry' option there were no problems found.