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Sound attenuation optimization using metaporous materials tuned on exceptional points
Lei Xiong1, Benoit Nennig2, Yves Aurégan1
1Laboratoire d'Acoustique de l'Université du Maine, Unité Mixte de Recherche CNRS 6613, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9, France.
The Journal of the Acoustical Society of America
|November 3, 2017
Summary
This study investigates metamaterials for enhanced sound attenuation in acoustic ducts. Optimal performance for low-frequency sound absorption is achieved when the material
Area of Science:
- Acoustics
- Materials Science
- Metamaterials
Background:
- Metamaterials offer unique acoustic properties.
- Enhancing sound attenuation in ducts at low frequencies remains a challenge.
Purpose of the Study:
- To investigate a metamaterial for improved sound attenuation in acoustic ducts.
- To identify optimal conditions for low-frequency sound absorption.
Main Methods:
- Experimental measurements of transmission loss.
- Numerical parametric studies of Bloch modes.
- Analysis of metamaterial properties including periodic inclusions and porous lining.
Main Results:
- A transmission loss peak was observed, linked to Bloch mode crossing.
- Optimum modal attenuation was found at the exceptional point.
- Metamaterial design parameters (inclusion position, frequency) were optimized.
Conclusions:
- Metamaterials can significantly enhance sound attenuation.
- Exceptional points offer a route to optimize metamaterial acoustic performance.
- The investigated metamaterial design shows promise for low-frequency noise control.
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