A forward advancing wave expansion method for numerical solution of large-scale sound propagation problems

Abstract

The study of atmospheric somid propagation has become an important subject since noise polhition problems emerged as a highly relevant matter in several areas such as sociology, economics, regulations and standards. Modelling sound propagation over large domains represents a major challenge for current numerical tools due the large computational resources required to obtain accurate solutions. In this thesis a “one-way” wave based field discretization method for solving the Helmholtz equation in large-scale problems is proposed and is referred to as the Forward Wave Expansion Method (FWEM). The FWEM is derived from a highly efficient discretization procedure based on interpolation of wave functions known as the Wave Expansion Method (WEM). The Wave Expansion Method (WEM) is a very flexible, efficient full field method for solving the Helmholtz equation, which uses mesh densities as low as 3 nodes per wavelength and can model complicated ground topography, ground impedance inhomogeneities and inhomogeneous moving media.