Acoustic metamaterial for low frequency sound absorption in linear and nonlinear regimes - Université de Bourgogne Accéder directement au contenu
Article Dans Une Revue Journal of Sound and Vibration Année : 2020

Acoustic metamaterial for low frequency sound absorption in linear and nonlinear regimes

Résumé

Acoustic metamaterial absorbers have been built and tested with focus on low frequency airborne sound absorption in linear and nonlinear regimes. The absorbers are made up of a series of piled up flat cavities, separated by thin walls and traversed by a perforation at their centre. A model for absorber effective properties is developed and compared with experimental data. The model is used to derive simple formulae for the frequency and the peak value of the absorption coefficient at the lowest frequency resonance, depending on the geometrical parameters of the structure. Different absorbers have been built with several cavity thicknesses to allow comprehensive comparisons with the model. Nonlinear properties of the absorbers are investigated experimentally using sine wave excitation around the resonance frequency with the amplitude of the incident wave up to 250 Pa. Flow resistivity measurements at low flow rates show that the periodic set of cavities does not modify resistivity significantly when compared to a simple perforated cylinder with same thickness. As flow rate increases, the flow resistivity grows linearly according to Forchheimer's law and has a significant dependence on the absorber thickness. A numerical model is developed accounting for the linear growth of flow resistivity with particle velocity amplitude in the central perforation and compared with the measurements at high amplitudes of the incident wave.
Fichier principal
Vignette du fichier
Brooke2020.pdf (652.85 Ko) Télécharger le fichier
Origine : Publication financée par une institution
Loading...

Dates et versions

hal-02953104 , version 1 (29-09-2020)

Licence

Paternité

Identifiants

Citer

Daniel C. Brooke, Olga Umnova, Philippe Leclaire, Thomas Dupont. Acoustic metamaterial for low frequency sound absorption in linear and nonlinear regimes. Journal of Sound and Vibration, 2020, 485, pp.115585. ⟨10.1016/j.jsv.2020.115585⟩. ⟨hal-02953104⟩
141 Consultations
99 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More