Multiple subcases in a part or assembly model are allowed. Any/all of them can be active at the same time.
Multiple subcases are essential to complete model definitions for Analysis Types of Linear Buckling, Prestress Static, Prestress Normal Modes and Nonlinear Buckling and they are done by default.
As shown in the above figure, Subcase 1 (Initial Stress Case) has a constraint and a load, but Subcase 2 (Linear Buckling Case) does not have any loads, and it includes the same constraint. This type of definition is needed for a linear and nonlinear buckling analysis, and is done by default.
Subcase 2 may have a different load but the same constraint as Subcase 1. This can be useful in a static analysis with multiple load cases on a part with the same constraints.
Autodesk Nastran analyzes all the subcases and calculates the results in a single analysis.
Right-click on Subcase X (Subcase sub-level) to access the following:
- Edit: This provides an alternative way to edit the content of the subcase. Loads and constraints can be selected from their respective area to be added to the subcase.
- Copy: Copies the selected subcase.
- Paste: Pastes the selected subcase.
- Rename: This allows you to rename Subcase 1 (typically).
- Activate: This toggle allows you to activate the subcase.
- Delete: Deletes the selected subcase.
- SPC Summation: This allows you to do single point constraint (SPC) force and moment summation only if single point constraint output is requested .