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.
https://hal-univ-lemans.archives-ouvertes.fr/hal-02458841 Contributeur : Olivier DAZELConnectez-vous pour contacter le contributeur Soumis le : dimanche 13 février 2022 - 09:33:14 Dernière modification le : mercredi 23 février 2022 - 14:29:06 Archivage à long terme le : : samedi 14 mai 2022 - 18:07:49
Clément Lagarrigue, Jean-Philippe Groby, Vincent Tournat, Olivier Dazel, Olga Umnova. Absorption of sound by porous layers with embedded periodic arrays of resonant inclusions. Journal of the Acoustical Society of America, Acoustical Society of America, 2013, 134 (6), pp.4670-4680. ⟨10.1121/1.4824843⟩. ⟨hal-02458841⟩