v8.21.301 ADLV301 — Cavity-plate coupling problem

Summary:

The objective of this test case is to calculate the pressure fields in a cavity in which one of the walls is flexible, the other walls being perfectly rigid. The excitation is mechanical and consists of a normal point force applied to the flexible wall.

Vibro-acoustic finite elements are used (modeling A: 3D_ FLUIDE and FLUI_STRU)

The boundary conditions are purely mechanical. They make it possible to create a deformation on the flexible wall, deformed which is the source of the acoustic field in the cavity. The transmission between the plate and the cavity field is managed by « fluid-structure » interface elements, specific to vibro-acoustic finite element modeling.

The dimensions of the cavity are sufficiently large and the thickness of the plate is small so as to observe a non-negligible coupling effect. In addition, the excitation is decentered in order to create a three-dimensional displacement field on the plate and an acoustic field in the cavity.

An exact analytical solution exists. This test case therefore makes it possible to validate the consideration of fluid-structure coupling. On the other hand, this test case validates the calculation of sound pressure in vibro-acoustic finite elements.

• 1. Reference problem
  • 1.1. Geometry
  • 1.2. Material properties
  • 1.3. Boundary conditions and loads
• 2. Benchmark solution
  • 2.1. Calculation method used for the reference solution
  • 2.2. Benchmark results
  • 2.3. Uncertainty about the solution
  • 2.4. Bibliographical references
• 3. Modeling A
  • 3.1. Characteristics of modeling A
  • 3.2. Characteristics of the mesh
  • 3.3. Tested sizes and results
• 4. Summary of results