The designed geometry can be extended by virtual elements for a simplified flow simulation (CFD).
Real and virtual geometry can coexist in the project, but can be visualized in the 3D-View and exported separately.
The real geometry represents the real design including the secondary flow path geometry for the impeller. If the model does not contain any secondary flow path, the real impeller geometry corresponds to the isolated impeller.
The virtual geometry has 2 objectives:
1)Simplification of the flow domain by neglecting the secondary flow path to accelerate CFD simulation.
Of course, deviations from the real flow behavior of the machine occur, but a qualitative comparison of different geometries is usually still possible.
2)Closing the necessary gap between the rotating impeller and adjacent static components.
Please note: In the 3D model, the extension is part of the impeller solid "Flow domain (virtual)". The rotor-stator-interface (RSI) is the border to the neighboring component. On the other side, the RSI connection is part of the neighboring component solid "Flow domain (virtual)".
In the 3D model, both geometries can be displayed independently using the proper tree nodes or selecting the corresponding model state: