

1) Check in the lower right-hand corner for the current system of units.
2) If the current system of units is not English units (in, lb, s), click on the box to bring up the User Options form.
3) Click Standard Units.
4) Scroll down and select the line with units in, lb, s,…
5) Click OK and OK.
6) Pull down Tools > Options.
7) Expand Input/Output.
8) Highlight Nastran.Structures.
9) Uncheck Reduce Parts.
10) Click OK.


1) Right-click pressure_hull.bdf and select Create new Nastran job.
2) Enter submarine for Job Name.
3) Select Linear Buckling Analysis (SOL 105) for Solution Type.
4 If desired, click the folder icon for Solver Input File and select a location to save analysis files.
5) Click OK.
6) Double-click Loadcase Control under Eigenvalue Extraction.
7) Highlight Eigenmode Extraction.
8) Select Lanczos for Method.
9) Enter 5 for Number of Desired Roots.
10) Select Maximum for Result Normalization Method.
11) Click Apply and Close.


1) Right-click any Part and select Show All.
2) Hide the display of Boundary Condition Symbols.
3) Under the Results tab, click Deformation.
4) Highlight Mode 1 for the Result Case.
5) THighlight Eigenvectors, Translational for Result type.
6) Click the Deformation tab.
7) Select Wireframe for the Deformed Shape Render style.
8) Uncheck Show undeformed box.
9) Click Update.





1) Click the Plot Data tab.
2) Highlight Mode 3 for the Result Case.
3) Click the Deformation tab.
4) Select Wireframe for Render style.
5) Select the color White for Edge color.
6) Check Show undeformed.
7) Select Wireframe for Undeformed shape Render style.
8) Select the color Red for Undeformed shape Edge color.
9) Click Update . Note the Buckling Load Factor .


