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Updated: Sep 6, 2025
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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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Moth wings as sound absorber metasurface
Thomas R Neil1, Zhiyuan Shen1, Daniel Robert1
1School of Biological Sciences, University of Bristol, Bristol, UK.
Proceedings. Mathematical, Physical, and Engineering Sciences
|June 27, 2022
Summary
Moth wings act as natural, deep-subwavelength sound absorbers, reducing noise reflection by up to 87%. Their unique scale structure and orientation are key to this bioinspired sound mitigation capability.
Area of Science:
- Acoustics
- Materials Science
- Bioinspired Engineering
Background:
- Metasurface absorbers aim for deep-subwavelength performance in noise control, a challenging technological goal.
- Natural structures like moth wings exhibit sound absorption properties due to their complex surface features.
Purpose of the Study:
- To investigate the potential of moth wings as natural metasurface sound absorbers.
- To quantify their sound absorption efficiency and understand the role of their unique structures.
Main Methods:
- Experimental measurement of sound reflection reduction by moth wings on acoustically reflective substrates.
- Analysis of the effect of scale removal and wing orientation on absorptive performance.
- Numerical simulations to explore the influence of air gaps and scale presence.
Main Results:
- Moth wings achieved up to 87% sound reflection reduction at 20 kHz, with a thickness to wavelength ratio as low as 1/50.
- Scale removal and reversed wing orientation significantly altered sound absorption, highlighting the importance of scales and air gaps.
- Numerical simulations confirmed the critical role of scales and the underlying air gap in absorption.
Conclusions:
- Moth wings function as effective deep-subwavelength sound-absorbing metasurfaces.
- The findings open avenues for bioinspired, high-performance acoustic mitigation solutions.
- The specific arrangement of scales and the air gap are crucial for the observed sound absorption properties.
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