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Engineering Acoustic Metamaterials for Sound Absorption: From Uniform to Gradient Structures
Xiuhai Zhang1, Zhiguo Qu1, Hui Wang2
1Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, P.R. China.
Iscience
|May 15, 2020
Summary
Recent advances in phononic crystals (PCs) and acoustic metamaterials (AMs) offer new solutions for sound absorption, particularly for low frequencies and broad working bands. Gradient-index AMs show promise for next-generation acoustic energy management and wave attenuation.
Area of Science:
- Acoustics and Materials Science
- Focuses on the physics of sound and the development of advanced materials for acoustic applications.
Background:
- The challenge of sound absorption has persisted for over two centuries, evolving with technological advancements.
- Phononic crystals (PCs) and acoustic metamaterials (AMs) have emerged as key areas of research in the last 30 years, addressing limitations in traditional sound absorption.
- These materials offer potential for broad working bands and effective low-frequency sound absorption.
Purpose of the Study:
- To review recent progress in sound absorption technologies, encompassing both airborne and waterborne applications.
- To highlight the advancements in gradient-index acoustic metamaterials (AMs) due to their unique properties.
- To explore the future potential of PCs and AMs in acoustic energy management and wave attenuation.
Main Methods:
- Review of recent scientific literature on phononic crystals and acoustic metamaterials for sound absorption.
- Analysis of gradient-index AMs, focusing on their impedance matching, dissipation mechanisms, and propagation path characteristics.
- Synthesis of findings related to airborne and waterborne sound absorption applications.
Main Results:
- Phononic crystals and acoustic metamaterials demonstrate significant potential for broad working band and low-frequency sound absorption.
- Gradient-index AMs exhibit favorable impedance matching, efficient viscous and thermal dissipation, and extended acoustic path lengths.
- Recent progress indicates these materials can effectively manage acoustic energy and attenuate waves.
Conclusions:
- Phononic crystals and acoustic metamaterials represent a promising frontier for next-generation sound absorbing materials.
- These advanced materials have the potential to trap and reuse acoustic energy, leading to more efficient sound management.
- Future applications may include the attenuation of seismic and tsunami waves, showcasing the versatility of these acoustic technologies.
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