3. Modeling A#

3.1. Characteristics of modeling#

_images/Object_7.svg

3.2. Characteristics of the mesh#

Number of knots: 2464

Number of meshes and types: 834 TRIA7

3.3. Tested sizes and results#

Identification

Reference

% difference

Critical pressure (\(n\mathrm{=}8\))

1.523 106 Pa

10.715

3.4. notes#

Critical pressure is tested without difficulty.

On the other hand, it is difficult to test the buckling mode because it is a dual mode.

The validation of this buckling mode is carried out in the following way:

  1. The coordinates of the mesh are modified very slightly (from 1.e-8) so that the mode associated with n=8 is the same, at each execution, on all the machines where the test is executed. (We de-symmetrize the problem a bit).

  2. It is visually validated that buckling modes 7 and 8 do have a shape with 8 lobes (see images below).

  3. We check (with a non-regression test) that mode 8 remains the same as the code evolves.

_images/100000000000035600000334FEEF9F081A02AE7E.png _images/1000000000000356000003346C6D2C778347EEEC.png

Note:

For the 4 models in this test, the fineness of the mesh is insufficient to properly represent the shape of the mode. This explains why the observed mode is not rigorously symmetric when rotated by 45 degrees.

It was verified that the symmetry was improved with a finer mesh. But, in order to maintain a rapid test, the coarse mesh is retained.