Transmission Properties of Two-Dimensional Chirped Phononic Crystal

Abstract

The mechanical wave transmission was investigated by a two-dimensional structure made of rods with a periodic arrangement-as the base structure. Compared structures had the same network constant in the direction perpendicular to the propagation of the acoustic wave, while the distances of subsequent layers of phononic crystal increased by a certain factor k. Depending on parameter k, chirped phononic crystal transmission properties were tested. The numerical analysis uses the finite difference time domain algorithm. The discrete Fourier transform allowed to determine the frequency characteristics of the tested systems. In order to verify numerical data, the experimental data was analyzed.

Influence of spatial distribution and the type of material on the occurrence of bandgaps in phononic crystals

“…The influence of layer thickness on transmission in one-dimensional structures made of amorphous materials was also analyzed [31]. The occurrence of numerically and experimentally gaps has been demonstrated in [32]. Much of the work related to phononics crystals focuses on topology optimization [33]- [37].…”