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Rapid Repetition Rate Fluctuation Measurement of Soliton Crystals in a Microresonator
Published on: December 15, 2021
Matryoshka locally resonant sonic crystal.
Daniel P Elford1, Luke Chalmers, Feodor V Kusmartsev
1Department of Physics, Loughborough University, Loughborough, LE11 3TU, United Kingdom. D.Elford@lboro.ac.uk
The Journal of the Acoustical Society of America
|November 18, 2011
Summary
Researchers developed novel sonic crystals using resonant elements, like Matryoshka configurations, to create low-frequency band gaps for effective sound barriers. This innovation offers new solutions for noise control in previously inaccessible ranges.
Area of Science:
- Acoustics
- Materials Science
- Solid State Physics
Background:
- Conventional sonic crystals primarily rely on Bragg scattering for sound attenuation.
- Low-frequency sound attenuation remains a significant challenge for traditional noise barrier technologies.
- Locally resonant structures offer potential for manipulating acoustic properties at sub-wavelength scales.
Purpose of the Study:
- To investigate the acoustic properties of sonic crystals incorporating resonant array elements.
- To propose and analyze the concept of locally resonant sonic crystals for broadband low-frequency sound attenuation.
- To evaluate the effectiveness of different resonant element configurations, including Matryoshka designs, for noise barrier applications.
Main Methods:
- Numerical modeling using finite element methods (FEM).
- Computation of acoustic band structure and transmission characteristics.
- Analysis of resonant element behavior and their contribution to band gap formation.
Main Results:
- The study demonstrates the formation of broad band gaps significantly below the first Bragg frequency.
- A distinct attenuation mechanism associated with resonant elements enhances low-frequency performance.
- The Matryoshka sonic crystal configuration shows optimal broadband attenuation in the lower frequency regime.
- Reduced crystal size is maintained while achieving significant low-frequency sound blocking.
Conclusions:
- Locally resonant sonic crystals offer a viable strategy for creating sound barriers effective in the low-frequency range.
- Matryoshka sonic crystals provide a promising configuration for broadband low-frequency noise control.
- This research opens new avenues for designing advanced acoustic materials and noise mitigation solutions.
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