7. Summary of results

Modeling COQUE_3D

The results obtained are satisfactory. Uncertainties about critical pressure do not exceed:

• \(\text{10.71\%}\) with TRIA7 meshes,

• \(\text{2.3\%}\) with QUAD9 meshes.

The modal deformation obtained corresponds well to the expected circumferential mode: \(n\mathrm{=}8\) for both models.

It can be seen that modeling COQUE_3D with mesh QUAD9 is more accurate than modeling COQUE_3D with mesh TRIA7.

Modeling DKT

The results obtained are satisfactory for plate elements. Uncertainties about critical pressure do not exceed \(\text{12.5\%}\) regardless of the mesh (QUAD4, TRIA3).

The modal deformation obtained corresponds well to the expected circumferential mode: \(n=8\) for both models.

This test made it possible to test models COQUE_3D and DKT in linear Euler buckling of a thin structure subjected to external pressure.