Automatic Surface Repair

The Automatic Surface Repair operation provides an automatic procedure for correcting a range of geometric type problems that can exist in the remeshed surface once the surface remeshing process is complete.

The Automatic Surface Repair operation is typically used when performing surface remeshing on a wrapped surface.

Repairing the surface before you execute the volume mesh operation increases the chance of success for the subsequent volume mesh operation. Use the Automatic Surface Repair operation before the relevant volume mesh operation when the simulation contains:
  • Complex geometries
  • Unreliable CAD data
  • Geometries with several defects
For anisotropic quadrilateral meshes, you are advised to use the Surface Remesher operation instead of the Automatic Surface Repair Operation.

Up to three different metrics are used to determine if automatic fixes are required:

  • Pierced Faces (surface intersections including opposing intersections)
  • Surface Proximity
  • Surface Quality

The metric for pierced faces is always on and is invoked when the Automatic Surface Repair operation is activated. The operation uses a distance based intersection calculation to flag and correct any potential surface intersection contained within the geometry. The metric for surface proximity is only used if the surface proximity property has been activated for the surface remesher. The metric for minimum quality is only used when the surface remesher has a minimum face quality value of greater than 0.

Within each metric, two different fixing mechanisms are used, arranged in best to worst order in terms of preserving the original geometry. The fixing mechanisms are:

  1. Remesh - Grows out the problem area and then surface remeshes, removing features if necessary.
  2. Patch - Grows out the problem area, deletes the local surface, and then invokes the hole filler.

These options can be accessed by selecting the Meshers > Automatic Surface Repair node:



The connected surface count limit can be used to control the number of individual isolated or disconnected surfaces. For example, if you are only expecting to have one surface at the end of the resurfacing process, then set a value of 1. The surface with the largest face count or area is retained while all others are eliminated. Alternatively or in addition, the connected surface size limit can be used to specify the minimum face count and/or area that each disconnected surface requires. The above two options can be used separately or in tandem in order to control the resultant surface.

If you remove the Automatic Surface Repair from an Automated Mesh operation, Simcenter STAR-CCM+ saves any user-defined settings and restores them if you reactivate Automatic Surface Repair.

The Automatic Surface Repair process does not fix topological problems such as free edges, non-manifold edges, and non-manifold vertices. Therefore, if these problems exist with the input surface, they must be fixed by hand afterwards using the Surface Repair tool.