Analysis of transient acoustic scattering by an elastic obstacle

Peijun Li; Lei Zhang

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arXiv · 1811.12480

Analysis of transient acoustic scattering by an elastic obstacle

Peijun Li·Lei Zhang

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Abstract

Consider the scattering of an acoustic plane wave by a bounded elastic obstacle which is immersed in an open space filled with a homogeneous medium. This paper concerns the mathematical analysis of the coupled two- and three-dimensional acoustic-elastic wave propagation problem in the time-domain. A compressed coordinate transformation is proposed to reduce equivalently the scattering problem into an initial-boundary value problem in a bounded domain over a finite time interval. The reduced problem is shown to have a unique weak solution by using the Galerkin method. The stability estimate and an a priori estimate with explicit time dependence are obtained for the weak solution. The reduced model problem is suitable for numerical simulations. The proposed method is applicable to many other time-domain scattering problems imposed in open domains.

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Peijun Li, Lei Zhang. 2018-11-29. Analysis of transient acoustic scattering by an elastic obstacle. https://arxiv.org/abs/1811.12480

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