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Quasi-zero stiffness resonators: Breaking low-frequency sound absorption limits
Chao Shen1, Tianquan Tang2, Yu Liu3
1School of Chemical Engineering and Energy Technology, Dongguan University of Technology, Dongguan 523808, China.
The Journal of the Acoustical Society of America
|September 24, 2025
Summary
This study introduces a novel quasi-zero stiffness (QZS) resonator using magnetic negative stiffness to overcome traditional sound absorption limitations. The QZS structure achieves broader bandwidth at lower frequencies for effective noise control.
Area of Science:
- Acoustics
- Materials Science
- Mechanical Engineering
Background:
- Traditional acoustic resonators struggle with low-frequency absorption and bandwidth without increased volume.
- This limitation hinders compact and efficient low-frequency noise control solutions.
Purpose of the Study:
- Introduce a novel sound absorption mechanism using a two-hollow magnet quasi-zero stiffness (QZS) structure.
- Overcome the performance limitations of conventional Helmholtz resonators for low-frequency noise control.
Main Methods:
- Theoretical modeling to understand the QZS mechanism.
- Finite element simulation for detailed analysis.
- Experimental validation using an impedance tube for performance verification.
Main Results:
- Magnetic negative stiffness significantly reduces effective stiffness, enabling wider bandwidth at lower frequencies.
- The QZS resonator's effective cavity height (Heff) can exceed optimal limits for traditional resonators.
- Achieved up to 1.6 times the physical length without increasing structural volume, surpassing conventional Helmholtz resonators.
Conclusions:
- The QZS structure offers a novel approach to compact, high-performance sound absorbers.
- Provides valuable theoretical and practical insights for designing advanced acoustic devices.
- Potential applications include aero-engine acoustic liners and underwater noise reduction systems.
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