Ground effect analysis: Surface wave and layer potential representations

Abstract This paper presents two kinds of analytical exact expressions of the sound field reflected by a plane boundary, as obtained by using either surface wave or layer potentials representations. Both solutions are first expressed as a sum of integrals which have a form suitable for numerical computation. Then these integrals are expanded into convergent series which provide analytical approximations of the solution. Numerical techniques are proposed for computing (a) the surface wave representation and (b) the approximation deduced from the layer potentials representation. This approximation and the classical one (sum of the surface wave and the first two terms of the asymptotic series) are compared with the exact solution. Several examples show that the approximate formulas established here are valid on a range much wider than the validity domain of the classical ones.

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