Preparing the Geometry

In general, a Simcenter STAR-CCM+ analysis requires one or more geometry parts from which you define the spatial construction of the regions. Simcenter STAR-CCM+ allows you to create geometry parts directly using the built-in 3D-CAD modeler, or import geometry from a wide range of source formats.

Complete the layout planning stage before starting this workflow.
  1. Provide initial geometry using one of the following methods:
    When importing geometry, on the import options dialog, retain Create Part Contacts from Coincident Entities as activated unless you have a specific reason not to.
  2. If you created geometry using 3D-CAD, convert the 3D-CAD model to equivalent geometry parts.
    See Creating geometry parts from 3D-CAD.
  3. Check the validity of parts and repair them when necessary:
    1. For imported CAD parts, run the CAD repair tool.
    2. For non-CAD parts, or if the CAD repair tool could not fix all issues for imported CAD parts, run the surface repair tool. See Repairing the surface.
  4. If necessary, position parts so that they align correctly. See Transforming parts.
  5. If the geometry parts represent the solid components only, and you require the complementary fluid volume, extract the fluid volume. See Extracting the fluid volume.
  6. In some cases, adjacent part surfaces can overlap without having any common edges around the overlapping area. To create common edges, which is essential for a quality mesh, imprint the overlapping parts. See Imprinting adjacent parts.
  7. Expand the Geometry > Contacts node and review the part contact objects.
    A part contact references two parts that are adjacent to each other. When both geometry parts are transferred to the regions domain, Simcenter STAR-CCM+ uses the part contact information in creating interfaces (for boundary-based interfaces). You can also use the same information in creating parts-based interfaces.

When you prepare your geometry for a Simcenter STAR-CCM+ simulation, consider the physics models that you are going to be using in the simulation.

For example, if you are modeling fluid flow through a valve:

  • assign an inlet boundary to the surface where fluid enters
  • assign an outlet or pressure boundary to the surface where fluid leaves.

To assign boundaries to surfaces, there must be separately selectable surfaces for both boundaries. To split surfaces at the geometry stage, use the following tools: