Related Experiment Video
Updated: May 28, 2025
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
15.3K
Interlayer Parallel Connection of Multiple Helmholtz Resonators for Optional Broadband Low Frequency Sound Absorption
Xiaocui Yang1,2, Qiang Li3, Xinmin Shen4
1Engineering Training Center, Nanjing Vocational University of Industry Technology, Nanjing 210023, China.
Materials (Basel, Switzerland)
|February 13, 2025
Summary
A novel acoustic metamaterial, the interlayer parallel connection of multiple Helmholtz resonators (IPC-MHR), effectively reduces low-frequency noise. Optimized IPC-MHR designs achieve high sound absorption coefficients, offering practical noise suppression solutions.
Area of Science:
- Acoustics
- Materials Science
- Noise Reduction
Background:
- Helmholtz resonance acoustic metamaterials are key for low-frequency noise reduction.
- A challenge exists in balancing resonator number and cavity volume within a given area.
- Single-layer metamaterials face limitations in achieving desired sound absorption.
Purpose of the Study:
- To propose a novel acoustic metamaterial, the interlayer parallel connection of multiple Helmholtz resonators (IPC-MHR).
- To investigate and optimize the sound absorption properties of the IPC-MHR.
- To demonstrate the practical application potential of IPC-MHR for noise suppression.
Main Methods:
- Finite element simulation was used to study sound absorption.
- Particle swarm optimization algorithm was employed for property optimization.
- Additive manufacturing and standing wave tube measurement validated the simulation results.
Main Results:
- A four-layer IPC-MHR achieved an average sound absorption coefficient of 0.7769 in the [200-300] U [400-600] U [800-1250] Hz band.
- Optimized IPC-MHR designs showed enhanced performance, with one achieving 0.8068 in 250-750 Hz.
- A six-layer optimized IPC-MHR reached an average coefficient of 0.8454 in 300-950 Hz.
Conclusions:
- The IPC-MHR demonstrates excellent wide-band, low-frequency sound absorption performance.
- The proposed metamaterial design overcomes limitations of traditional single-layer structures.
- IPC-MHR holds significant potential for practical applications in noise reduction.
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