Using Driving Dimensions in Ansys
You can create driving dimension groups in SpaceClaim and use them to change key dimensions in Ansys. Just select the part in the structure tree in Ansys and find the CAD Parameters section in the Details panel. Change a value and run the analysis again to see its affect. You can use Update to send the new values back to SpaceClaim.
Creating a driving dimension with Move (translation or rotation)
Creating a driving dimension with the Select tool (round radius and distance between offset faces)