The insertion loss of screens under the influence of wind

Abstract

Point source propagation over a screen located on a finite impedance surface representative of grass-covered ground is investigated under upwind and downwind conditions. The theoretical part of the investigation involves extended use of parabolic equation methods (PE) allowing for the changes in the vertical wind speed profile when the wind field passes the screen. The influence of turbulence is also implemented. The experimental part of the investigation relies on a scale model technique based upon a 1:25 scaling ratio and a triggered spark source. The main results relate to the size of the insertion loss of a screen under windy conditions and to the acoustic importance of the redirection of the flow before and after the screen.