A hybrid BIE/FFP scheme for predicting barrier efficiency outdoors

Abstract

To assess the acoustical performance of noise screens in the presence of an arbitrary sound speed profile, a numerical scheme based on a combination of the boundary integral and fast field program methods is developed. The Green’s function required in the boundary integral is evaluated by a fast field formulation. The procedure is validated by comparing its predictions with other numerical results for simple cases and with measurements for indoor model experiments simulating downward refracting conditions. It is predicted that the performance of a noise screen placed 50 m from the source is reduced considerably by moderate downwind conditions.