A substructuring approach for modeling the acoustic scattering from stiffened submerged shells coupled to non-axisymmetric internal structures

Autor: Laurent Maxit, Christian Audoly, Valentin Meyer
Přispěvatelé: Laboratoire Vibrations Acoustique (LVA), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA), DCNS Research, ANR-11-IDEX-0007,Avenir L.S.E.,PROJET AVENIR LYON SAINT-ETIENNE(2011), Laboratoire Vibrations Acoustique ( LVA ), Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Université de Lyon-Institut National des Sciences Appliquées ( INSA )
Rok vydání: 2016
Předmět:
Zdroj: Journal of the Acoustical Society of America
Journal of the Acoustical Society of America, Acoustical Society of America, 2016, 140 (3), pp.1609-1617. ⟨10.1121/1.4962235⟩
Journal of the Acoustical Society of America, Acoustical Society of America, 2016, 140 (3), pp.1609-1617. 〈10.1121/1.4962235〉
ISSN: 0001-4966
1520-8524
DOI: 10.1121/1.4962235
Popis: International audience; The scattered pressure from a stiffened axisymmetric submerged shell impinged by acoustic plane waves has been investigated experimentally, analytically and through numerical models. In the case where the shell is periodically stiffened, it is shown that helical, Bragg, and Bloch-Floquet waves can propagate. The influence of non-axisymmetric internal frames on these scattering phenomena is nevertheless not well known, as it can considerably increase the computational cost. To overcome this issue, the Condensed Transfer Function method, which has been developed to couple subsystems along linear junctions in the case of a mechanical excitation, is extended to acoustical excitations. It consists in approximating transfer functions on the junctions and deducing the behavior of the coupled system using the superposition principle and the continuity equations at the junctions. In particular, the CTF method can be used to couple a dedicated model of an axisymmetric stiffened submerged shell with non-axisymmetric internal structures modeled by the Finite Element Method. Incident plane waves are introduced in the formulation and far-field reradiated pressure is estimated. An application consisting of a stiffened shell with curved plates connecting the ribs is considered. Supplementary Bloch-Floquet trajectories are observed in the frequency-angle spectrum and are explained using a simplified interference model.
Databáze: OpenAIRE