Multi-Body Instancing

In Simcenter STAR-CCM+, you can import CAD models that include multiple instances of the same body. You can apply changes to all instances at the same time by modifying a single instance, which acts as a reference to all other instances.

  1. To import a multi-instanced body, right-click 3D-CAD Model and select Import > CAD Model.
  2. Select the file you want to import and activate Import Multi-instanced Bodies. Click Open.

    You can copy and apply any modifications from one instance to all other instances. For example, to apply a constant radius fillet to all instances:

  3. To create a fillet, right-click an edge on the body and select Create Fillet. Set the desired radius and tolerance for the fillet.
  4. In the Body Instances panel, select Apply to all the Instances.
  5. To exclude bodies, select Excluded Body Instances and select bodies you want to exclude.

    A badge is added to the instanced bodies icon () and the Multi-Instanced property is activated automatically.

  6. To view all multi-instanced bodies in a model, in the feature tree, right-click 3D-CAD Model > Show Only Multi Instanced Bodies.
  7. To see instances of a particular body, right-click the desired body node in the feature tree and select Show Only Instances.
  8. To view specific instanced faces, edges, vertices, or bodies, select Selection () > Select Instances ().
  9. To convert a multi-instanced body to a flat body, right-click the desired body and select Convert to Flat Body.


When Apply to all the instances is deactivated, the operation is applied only to the selected body.

The following features support multi-body instancing:
  • Fillets with constant radius. Fillets with a variable radius are not supported.
  • Chamfer
  • Delete Faces/Bodies
  • Copy Bodies
  • Move Body
  • All Repair Feature tools excluding Repair CAD and Zip Edges.
  • Shell
  • Extend Solid - Not supported if you select the Up to faces option.

  • Extend Surface (Partially) - If you select the Extension Method, Body/face is not supported.

  • All 2D/3D sketch commands
  • Transfer to PARTs - The bodies in 3D-CAD remains instanced but in PARTs they gets flattened as PARTs is not supporting instanced bodies.
  • Import CAD - When importing multi-instanced bodies, the option to import faceted bodies, repair invalid bodies, and split periodic faces are not supported.
Features that do not support instanced bodies are flattened before the feature operation is performed.