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Updated: May 24, 2026
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Wave propagation in a duct with a periodic Helmholtz resonators array.
1Department of Building Services Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
The Journal of the Acoustical Society of America
|February 23, 2012
Summary
Periodic Helmholtz resonators offer broader noise control by creating distinct sound pass and stop bands. This periodic arrangement enhances noise attenuation bandwidth and magnitude in ducts.
Area of Science:
- Acoustics
- Wave Propagation
- Mechanical Engineering
Background:
- Helmholtz resonators effectively reduce noise within narrow frequency bands.
- Broadening noise attenuation requires combining multiple resonators.
- Periodic arrangements of resonators are explored for enhanced acoustic performance.
Purpose of the Study:
- To theoretically investigate sound propagation in a 1D duct with periodically mounted identical side-branch resonators.
- To develop a distributed-parameter model for resonator analysis, improving resonant frequency prediction.
- To analyze wave coupling and dispersion effects in periodic resonator systems.
Main Methods:
- Utilized a distributed-parameter model for individual resonator analysis, incorporating multi-dimensional wave propagation.
- Applied Bloch wave theory and the transfer matrix method to study wave propagation in periodic structures.
- Validated theoretical predictions through 3D finite element method simulations and experimental measurements.
Main Results:
- The distributed-parameter model provided more accurate resonant frequency predictions than lumped-parameter models.
- Theoretical predictions aligned well with finite element simulations and experimental data.
- Wave coupling in the periodic system led to the formation of distinct stop and pass frequency bands.
Conclusions:
- Periodic resonator systems offer a viable strategy for broadening noise attenuation bandwidth.
- The study demonstrates the potential of periodic resonators for more effective noise control in ducts.
- Enhanced sound attenuation magnitude and bandwidth are achievable through periodic resonator design.
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