Crack objects dynamically generate Named Selections during crack mesh generation. The Named Selections generated for Arbitrary Crack and analytical crack objects are a special type of Named Selection and have the distinct properties listed below. Note that semi-elliptical, elliptical, ring, corner, edge, through, and cylindrical are analytical cracks.
Named Selections for analytical crack or Arbitrary Crack objects are not inserted into the Named Selections branch of the Tree Outline. They appear in the Outline under the analytical crack or Arbitrary Crack objects with which they are associated.
You may rename a Named Selection by editing its name in the Details of the analytical crack or Arbitrary Crack object or by right-clicking the Named Selection in the tree Outline and selecting Rename. Use caution when renaming the Named Selection associated with the crack front (NS_SECrack_Front). If the name is not unique when compared to other Named Selections, the crack definition sent to the solver may contain the wrong set of crack front nodes.
Important: For cracks with multiple crack fronts, the Crack Front Nodes property, under Named Selection Creation category, only modifies the first crack front name if you have already generated the mesh. However, the application applies the property value to all crack fronts if you are generating the mesh for the first time or if the mesh is re-generated.
For a Ring Crack, two crack front named selections are created at the outer and inner intersection of the crack with the solid body.
An Arbitrary Crack defined using an embedded or intersecting crack surface body could generate more than one crack front.
You cannot insert, duplicate, copy, delete, or merge these Named Selections.
You may scope nodal-based loads to these Named Selections.
By default, nodal Named Selections show nodes attached to them in the Geometry window. To plot elements attached to these nodal Named Selections, refer to Specifying Annotation Preferences section of the help.
If you delete analytical or Arbitrary Crack objects, all associated Named Selections are deleted.
If you suppress analytical or Arbitrary Crack objects, the nodal selection of each associated Named Selection is cleared and the state of each Named Selections becomes suppressed.
All Named Selections for analytical or Arbitrary Crack objects are sent to the solver. Send to Solver is always set to Yes and is read-only.
If Named Selections for Crack Faces Nodes and/or Contact Pairs Nodes have been created and you subsequently set the fields to Off, the corresponding Named Selections are deleted when a new crack mesh is generated.
See the Named Selections section of the Help for additional information.
Note: For information about common fracture meshing problems and troubleshooting, see Fracture Meshing Problems.