Importing Surfaces as Geometry Parts

The option to create a geometry part is selected by default when importing surface data.

Selecting the Create New Part option within the Import Mode group box presents the import options relevant to the file type being imported.

Depending on the type of surface file, the import process results in one or more leaf-level parts being created. Composite parts (assemblies) are also created when the original file supported and used this option. CAD parts are created when the original files contain neutral format data or native CAD data. Mesh parts are created when the original files contain surface mesh data.

The import parts process reads all CAD parts before tessellation begins. If a surface on a part fails to tessellate (due to invalidities in the CAD model), the tessellation process stops for that part and continues for the next part. All parts are imported into Simcenter STAR-CCM+, but those parts which failed to tessellate completely do not display correctly.

The Mark Feature Edges and Tessellation Density options are described within the section, Importing Surface Data into Simcenter STAR-CCM+. When the Create Part Contacts from Coincident Faces option is activated, part contact data is generated for parts that share coincident faces that are within the Coincident Face Tolerance distance from their neighbors. Do not use this option to create contacts or interfaces between parts that have large gaps between them. If parts have large gaps between them, move one part closer to the other using a translation operation. If the Merge Parts by Name option is selected, any two bodies in the imported assembly with the same name are merged into one part automatically. If the option is deactivated, each body in the assembly becomes its own part in Simcenter STAR-CCM+ regardless of its name.

To manage the hierarchy of various components to better suit the analysis in hand, geometry parts can be reorganized once they have been imported. Once organized, the meshing operations can be initialized to provide a starting input surface representation that is based on the currently selected geometry parts. In general, all the native CAD file formats plus the Parasolid Transmit format can maintain the same assembly hierarchy as the original CAD program that produced the geometry in the first place. Additionally, the part names are also carried over for these formats and, under certain circumstances, the names that are attached or tagged to faces are also translated. IGES data does not carry part names but STEP data will under certain circumstances. In this respect, the Parasolid Transmit file is the better export option out of all of the neutral file formats in terms of maintaining the organizational data structure.

The import of a geometry part also creates a Geometry representation in the Representation node. This node has no properties and is simply a place holder for indicating that geometry parts exist.