Multisector parabolic-equation approach to compute acoustic scattering by noncanonically shaped impenetrable objects

TL;DR

This paper advances parabolic equation methods for acoustic scattering by complex-shaped objects, introducing wide-angle and multiple-scattering approaches to improve accuracy for concave targets while maintaining computational efficiency.

Contribution

It presents novel modifications to traditional parabolic equation methods, enabling accurate modeling of concave scatterers and benchmarking against finite-element results.

Findings

Good agreement with finite-element results for convex scatterers

Enhanced accuracy for concave scatterers with the new approach

Significant computational efficiency at higher frequencies

Abstract

A lesser-known but powerful application of parabolic equation methods is to the target scattering problem. In this paper, we use noncanonically shaped objects to establish the limits of applicability of the traditional approach, and introduce wide-angle and multiple-scattering approaches to allow accurate treatment of concave scatterers. The PE calculations are benchmarked against finite-element results, with good agreement obtained for convex scatterers in the traditional approach, and for concave scatterers with our modified approach. We demonstrate that the PE-based method is significantly more computationally efficient than the finite-element method at higher frequencies where objects are several or more wavelengths long.