Analysis of the wave propagation properties of a periodic array of rigid cylinders perpendicular to a finite impedance surface

TL;DR

This paper investigates how a finite impedance surface influences wave propagation in a 2D periodic array of rigid cylinders, combining numerical and experimental methods to understand interactions affecting wave control devices like noise barriers.

Contribution

It provides a detailed analysis of the combined effects of surface impedance and array periodicity on wave behavior, advancing design strategies for wave control devices.

Findings

Interaction between surface reflection and array bandgap affects wave transmission.

Wave propagation properties depend on surface impedance.

Experimental and numerical results confirm the influence of impedance on bandgap characteristics.

Abstract

The effect of the presence of a finite impedance surface on the wave propagation properties of a two-dimensional periodic array of rigid cylinders with their axes perpendicular to the surface is both numerically and experimentally analyzed in this work. In this realistic situation both the incident and the scattered waves interact with these two elements, the surface and the array. The interaction between the excess attenuation effect, due to the destructive interference produced by the superposition of the incident wave and the reflected one by the surface, and the bandgap, due to the periodicity of the array, is fundamental for the design of devices to control the transmission of waves based on periodic arrays. The most obvious application is perhaps the design of Sonic Crystals Noise Barriers. Two different finite impedance surfaces have been analyzed in the work in order to observe the dependence of the wave propagation properties on the impedance of the surface.