Vibro-acoustic analysis of lightweight composite panels with damping materials

In this paper a numerical model to study the vibro-acoustic behavior of a laminated plate backed by a poroelastic foam layer is developed. Such approach consists on a coupled mitigation strategy aiming either mechanical vibration suppression or acoustic attenuation as well. The laminated plate model consists of fiber laminae with interleaved viscoelastic layers in standard constrained or integrated layer damping schemes, whereas surface mounted poroelastic foam materials are included. Mechanical and acoustic excitations in terms of incident plane waves are considered in this study. For the plate modeling, the finite element method considering a layerwise kinematic assumption is used. On the other hand, poroelastic treatments are developed based on the Biot's theory of poroelasticity. As a result, using the capabilities of the multi-layered model, different vibro-acoustic indicators characterizing the vibro-acoustic behavior of panels vibrating in an acoustic fluid are computed, namely, mean square velocity, radiation sound power, radiation efficiency and transmission loss of the coupled fluid-plate system. In addition, a study addressing the coupling between both solid and fluid phases of the poroelastic material in the plate-foam coupled design is performed aiming to study about the energy dissipation and sound mitigation performance of the poroelastic treatment.