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Low-Frequency, Open, Sound-Insulation Barrier by Two Oppositely Oriented Helmholtz Resonators
Yi-Jun Guan1,2,3, Yong Ge1, Hong-Xiang Sun1,3
1Research Center of Fluid Machinery Engineering and Technology, School of Physics and Electronic Engineering, Jiangsu University, Zhenjiang 212013, China.
Micromachines
|December 24, 2021
Summary
This study presents an ultrathin, open sound-insulation barrier using periodic subwavelength units. The innovative design offers effective low-frequency sound control and high ventilation, with potential for architectural acoustics.
Area of Science:
- Acoustics
- Materials Science
- Mechanical Engineering
Background:
- Traditional sound insulation methods often compromise ventilation.
- Achieving effective low-frequency sound insulation with thin structures remains a challenge.
Purpose of the Study:
- To develop and demonstrate a novel, ultrathin, open sound-insulation barrier.
- To achieve simultaneous low-frequency sound insulation and high ventilation.
Main Methods:
- Numerical simulations and experimental validation were employed.
- The barrier design utilizes periodic subwavelength units composed of Helmholtz resonators.
- A multilayer structure was investigated for broadband performance.
Main Results:
- A single-layer barrier achieved a minimum transmittance of 0.06 at 121.5 Hz.
- The barrier demonstrated effective low-frequency sound insulation and high ventilation.
- A four-layer barrier achieved a fractional bandwidth of approximately 0.19 for broadband sound insulation.
Conclusions:
- The proposed open sound-insulation barrier offers a promising solution for architectural acoustics and noise control.
- The design provides ultrathin thickness, omnidirectional sound insulation, broad bandwidth, and high ventilation.
- The multilayer barrier shows potential for ventilated rooms requiring soundproofing.
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