Apply the Loads

1. Right-click on Loads under Subcase 1 and choose New.
2. Change the Name to Pressure.
3. Change the Type drop-down to Pressure. Type -1 for Magnitude under Load Definition.
4. Be sure that Subcase 1 is selected in the Subcases list.
5. Select all the upper faces in the model, either individually, or by using a box pick method.
6. The Load dialog should look as shown below.

   

7. Click OK. The model should look as shown below.

   

8. In the Part tree, right-click on Subcase 1, select Rename and type in Linear Buckling Case.
9. Once finished, the tree view should look as shown below.