title: Absorption of sound by porous layers with embedded periodic arrays of resonant inclusions.
abstract: The aim of this work is to design a layer of porous material with a high value of the absorption coefficient in a wide range of frequencies. It is shown that low frequency performance can be significantly improved by embedding periodically arranged resonant inclusions (slotted cylinders) into the porous matrix. The dissipation of the acoustic energy in a porous material due to viscous and thermal losses inside the pores is enhanced by the low frequency resonances of the inclusions and energy trapping between the inclusion and the rigid backing. A parametric study is performed in order to determine the influence of the geometry and the arrangement of the inclusions embedded in a porous layer on the absorption coefficient. The experiments confirm that low frequency absorption coefficient of a composite material is significantly higher than that of the porous layer without the inclusions.
authors: LUNAM Université, Université du Maine, CNRS, LAUM UMR-CNRS 6613 (Laboratoire d'Acoustique de l'Université du Maine), Avenue O. Messiaen, 72085 Le Mans, France.
authors: C
authors: C
authors: Lagarrigue
authors: LUNAM Université, Université du Maine, CNRS, LAUM UMR-CNRS 6613 (Laboratoire d'Acoustique de l'Université du Maine), Avenue O. Messiaen, 72085 Le Mans, France.
authors: J P
authors: JP
authors: Groby
authors: LUNAM Université, Université du Maine, CNRS, LAUM UMR-CNRS 6613 (Laboratoire d'Acoustique de l'Université du Maine), Avenue O. Messiaen, 72085 Le Mans, France.
authors: V
authors: V
authors: Tournat
authors: LUNAM Université, Université du Maine, CNRS, LAUM UMR-CNRS 6613 (Laboratoire d'Acoustique de l'Université du Maine), Avenue O. Messiaen, 72085 Le Mans, France.
authors: O
authors: O
authors: Dazel
authors: Acoustics Research Centre, University of Salford, Salford, Greater Manchester, M5 4WT, United Kingdom.
authors: O
authors: O
authors: Umnova