Font Size:
Numerical Simulation of Sound Attenuation by Sonic Crystals
Last modified: 2016-05-23
Abstract
Sonic crystals are a type of acoustic metamaterials that exhibit spectral band-gap behavior, preventing sound waves of a band of frequencies from passing through the crystals. These crystals are typically made from a periodic arrangement of sound scatterers, and the central frequency of the band-gap is nominally given by Bragg’s law. By varying the geometry and arrangement of the of scatterers, specific band of frequencies can be filtered out or blocked off using a sonic crystal. In this study, we look at the attenuation of sound waves passing through a sonic crystal made up of several rows of scatterers. Numerical simulations were conducted using finite element software to obtain spectral of the insertion loss. The effectiveness of using this sonic crystal to mitigate noise was evaluated. Parametric studies were performed to determine the optimal geometry and layout of the sonic crystal to attenuate specific frequency spectrum of the noise. Helmholtz resonators are also incorporated to target lower frequency noise. This helps to complement the frequency band-gap generated by the sonic crystal, resulting in a broader band of sound attenuation for the entire structure. The numerical simulations are benchmarked and validated against experiments conducted on prototypes in the laboratory.
Keywords
Simulation, Finite Element, Sonic Crystal, Sound Attenuation
An account with this site is required in order to view papers. Click here to create an account.