In the tree view, right-click on
Analysis 1 and choose
Edit.
Type
Dome Lid Buckling for
Name, and type
Linear Buckling for
Title. Select
Linear Buckling from the
Type drop-down menu.
Click the
Options tab, and then enter
3 for the
Number of Modes to be extracted. This will instruct Autodesk Nastran to calculate the first 3 eigenvalues.
Click
OK to return to the tree view.
Save the model at this point.
In the tree view, right-click on
Constraints under
Subcase 1 and choose
New.
Rename the constraint to
Outer Face Fixed.
Orient the model inside
Inventor Nastran so that you can clearly view and pick the outer most upper face.
Be sure that
Subcase 1 is selected in the
Subcases list.
Accept the default settings and click
OK to create a fixed constraint.
Right-click on
Loads under
Subcase 1 and choose
New.
Change the
Name to
Pressure.
Change the
Type drop-down to
Pressure. Type
-1 for
Magnitude under
Load Definition.
Be sure that
Subcase 1 is selected in the
Subcases list.
Select all the upper faces in the model, either individually, or by using a box pick method.
The
Load dialog should look as shown below.
Click
OK. The model should look as shown below.
In the
Part tree, right-click on
Subcase 1, select
Rename and type in
Linear Buckling Case.
Once finished, the tree view should look as shown below.
Click
Save to save your work.
Right-click on the empty space of the tree view and select
Solve in Nastran.
Autodesk Nastran solves the model and displays the progress in the
Autodesk Nastran Output window inside
Inventor Nastran.
When you see the dialog "Nastran Solution Complete", click
OK to load the results into
Inventor Nastran.