Vibroacoustic response of an immersed stiffened multilayered shell excited by a plane wave

M. Dana (1, 2) , Laurent Maxit (1) , J. Bernard (2)

1 LVA - Laboratoire Vibrations Acoustique
2 TUS - Thales Underwater Systems (Thalès)

The modelling of the vibroacoustic response of a periodically rib-stiffened cylindrical multilayered shell is of great interest in numerous industrial applications, among which submarine acoustics. An approach is proposed in this paper to couple an immersed multilayered shell model with models of the axisymmetric stiffeners. The multilayered shell may be modeled either with the transfer matrix method (TMM) or with the direct global method (DGM). Both methods are spectral: displacements and stress are obtained in the wavenumber domain before reconstructing the solution in the physical domain. This allows us representing different types of layers: isotropic, orthotropic, fluid, etc. The stiffeners are coupled to the multilayered shell at the internal radius of the latter. They are introduced in the formulation by dynamic circumferential admittances which are estimated by classic finite element methods. To illustrate the method we'll present different results as much for validation as for comparison with the unstiffened shell.

Mots clés: Sound Insulation; Multilayer 3D; Heavy fluid loading; Stiffened shell; Stiffened structures; Sound; Insulation; Transmission

Domaines: Acoustique [physics.class-ph]

M. Dana, Laurent Maxit, J. Bernard. Vibroacoustic response of an immersed stiffened multilayered shell excited by a plane wave. Internoise, Aug 2018, Chicago, United States. ⟨hal-01922234v2⟩