8. Summary of results

• Shell modeling DKT, restricted here to modes with the 3 symmetries with respect to planes \(\text{x = 0}\), \(\text{y = 0}\), \(z=0\), provides natural frequencies with an error of less than \(\text{0.4\%}\) on the first 20 modes.

• The \(\mathrm{2D}\) axisymmetric continuous medium modeling provides the natural frequencies with an error of less than \(\text{2\%}\).

• Modeling COQUE_AXIS (quadratic isoparametric elements) provides the natural frequencies with an error of less than \(\text{0.2\%}\) on the first 5 modes (spatial discretization identical to the axisymmetric \(\mathrm{2D}\) mesh trace).

• Degenerate modeling COQUE_3D (thick shell elements MEC3QU9H, MEC3TR7H) provide natural frequencies with an error of less than \(\text{1.2\%}\) on the first 10 modes.