Importing Nastran Files

The command to import a mesh from an Nastran format file is:

Import Nastran [Mesh Geometry] '<input_filename>' [Feature Angle <angle>] [Nobcs]

Including the keyword Mesh Geometry will instruct CUBIT to create mesh-based geometry. This will provide the user with the ability to remesh geometric entities. If the user does not import with the Mesh Geometry flag, he will have to tell CUBIT to draw the mesh after the import is done in order to view it.

The Feature Angle is used when building the surface topology to determine when to split a surface into two surfaces. If the angle between two neighboring element normals is less than Feature Angle, then the two elements will be placed on separate surfaces. If the keyword Feature Angle is not supplied, the default 135 degrees is used. For a description of importing mesh geometry see Importing Exodus II Files.

It should be noted that CUBIT sometimes cannot successfully generate mesh-based geometry for complex models.  If this occurs, import the mesh without the Mesh Geometry flag, and draw the mesh to view it.

See http://en.wikipedia.org/wiki/Nastran for more information on the NASTRAN file format.