Sensitivity in response of multi-layered, finite size panels with anisotropic poro-elastic materials having non-aligned principal material directions

At LMSSC, Cnam, Paris, April 18th 2013, 14 p.m.

Peter Göransson
Professor, VinnExcellence Center for ECO2 Vehicle design, Marcus Wallenberg Laboratory for Sound and Vibration Research,
Department of Aeronautical and Vehicle Engineering, School of Engineering Sciences, KTH, Stockholm, Sweden

It is common knowledge that the different elastic-anelastic, acoustic-viscoacoustic interaction mechanisms governing the behaviour of porous materials, in general exhibit different degrees of anisotropicity depending on the type of material and the inherent micro-structural build. The sensitivity in the response due to relative alignment of multiple layers of anisotropic open cell porous materials is investigated for finite sized panels with different edge restraints, etc. The acoustic response is evaluated through numerical experiments using finite element solutions.

It will be shown that, depending on the degree of anisotropy of the porous material properties, their relative alignment may have a significant influence on the acoustic response. The influence of the boundary conditions between the layers and at interfaces to solid components will be illustrated. In the discussion the importance of the anisotropies as such, and the alignment, of these mechanisms will be highlighted, contributing to the currently ongoing discussion of further advancing the knowledge of anisotropic behavior.