A finite element study of acoustic wave propagation through sonic crystal

Abstract

A sonic crystal is periodic array of scatterers in which scatterers are embedded on a material having low impedance. Applications of the sonic crystals have led to a growing interest in the periodic structures embedded in a material. These periodic arrangements of scatterers have ability to stop sound waves within certain frequency bands. In this paper, we studied a 2-D sonic crystal in which circular scatterers are placed in rectangular grid. An array of scatterers in a homogeneous material is analyzed here and its transmission loss is computed. Bloch Floquet theorem is used to analyze this periodic structure. Eigenvalue study is also done using periodic boundary conditions on a single unit cell and result shows that there is a great amount of sound transmission loss (18 dB) due to the presence of the band gap in the sonic crystal. The obtained results of band gaps and transmission losses are compared with previous literature.