v8.21.101 ADLV101 - Sloping and acoustic modes of a parallelepiped tank filled with water#

Summary:

This test, in the acoustic and fluid field, focuses on the search for the natural frequencies of a compressible fluid domain, including a free surface, contained in a rigid parallelepiped tank. Modal analysis thus determines the first sloshing modes (in the presence of gravity) of the free surface of the fluid filling the tank, then the first acoustic modes.

The first eight natural sloshing frequencies are found at less than 1% of the frequencies calculated analytically. The first two acoustic natural frequencies are found at less than 1% of the frequencies calculated analytically.

The proposed models are:

modeling A: PHENOMENE =” MECANIQUE “, fluid elements \((p,\mathrm{\Phi },z)\) linear meshes;

B modeling: PHENOMENE =” MECANIQUE “, \((p,\mathrm{\Phi },z)\) quadratic Serendip fluid elements;

C modeling: PHENOMENE =” MECANIQUE “, quadratic \((p,\mathrm{\Phi },z)\) fluid elements;

D modeling: PHENOMENE =” MECANIQUE “, fluid elements \((p,\mathrm{\Phi },z)\) linear meshes;

E modeling: PHENOMENE =” MECANIQUE “, \((p,\mathrm{\Phi },z)\) quadratic Serendip fluid elements;

modeling F: PHENOMENE =” ACOUSTIQUE “, without sloshing, linear elements.