Noise propagation from a cutting of arbitrary cross-section and impedance

Peplow, A.T. and Chandler-Wilde, S. N. ORCID: https://orcid.org/0000-0003-0578-1283 (1999) Noise propagation from a cutting of arbitrary cross-section and impedance. Journal of Sound and Vibration, 223 (3). pp. 355-378. ISSN 0022-460X doi: 10.1006/jsvi.1999.2126

Abstract/Summary

A boundary integral equation is described for the prediction of acoustic propagation from a monofrequency coherent line source in a cutting with impedance boundary conditions onto surrounding flat impedance ground. The problem is stated as a boundary value problem for the Helmholtz equation and is subsequently reformulated as a system of boundary integral equations via Green's theorem. It is shown that the integral equation formulation has a unique solution at all wavenumbers. The numerical solution of the coupled boundary integral equations by a simple boundary element method is then described. The convergence of the numerical scheme is demonstrated experimentally. Predictions of A-weighted excess attenuation for a traffic noise spectrum are made illustrating the effects of varying the depth of the cutting and the absorbency of the surrounding ground surface.