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Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
Published on: June 28, 2024
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Acoustic radiation from a cylindrical shell with a voided soft elastic coating
Gyani Shankar Sharma1, Adrien Marsick2, Laurent Maxit2
1School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, Australia.
The Journal of the Acoustical Society of America
|January 1, 2022
Summary
This study presents a new acoustic coating for fluid-loaded cylindrical shells. The innovative design effectively reduces radiated sound across a wide frequency range.
Area of Science:
- Acoustics
- Materials Science
- Mechanical Engineering
Background:
- Fluid-loaded cylindrical shells are susceptible to acoustic radiation.
- Acoustic coatings can mitigate sound propagation.
- Designing effective coatings requires understanding complex material interactions.
Purpose of the Study:
- To develop an analytical framework for sound radiation from coated cylindrical shells.
- To investigate the acoustic performance of a novel coating.
- To demonstrate the tunability of the coating for sound reduction.
Main Methods:
- Modeling an acoustic coating with a void layer as an effective fluid.
- Deriving expressions for coating impedance, shell displacement, and radiated pressure.
- Analyzing harmonic excitation of the coated shell.
Main Results:
- The proposed coating significantly reduces sound radiation.
- The coating's performance is tunable by adjusting its design parameters.
- Broadband sound reduction is achievable with this coating.
Conclusions:
- The analytical framework is effective for predicting sound radiation.
- The novel acoustic coating offers a promising solution for noise reduction.
- Coating design optimization can lead to substantial improvements in acoustic performance.
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