I already tried making a multibody part in SW, but when importing into ANSYS, it is still seen as 2 separate bodies with automatic contact between the two parts.
The only way to get Shared Topology is to use either SpaceClaim or DesignModeler. If you have one of those, they can open a Parasolid from SolidWorks, then you can create a Multibody part and Share Topology.
If you don't want to do that or don't have those licenses, then you can imprint the larger face with the outline of the smaller face to get idendtical faces, then use Mesh Controls to get a congruent mesh on both faces, and finally to use Mesh Merge. That ends up being equivalent to Shared Topology, but is more work.
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