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arXiv · 2011.07434

Time-Domain Multiple Traces Boundary Integral Formulation for Acoustic Wave Scattering in 2D

Carlos Jerez-Hanckes·Ignacio Labarca
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Abstract

We present a novel computational scheme to solve acoustic wave transmission problems over composite scatterers, i.e. penetrable obstacles possessing junctions or triple points. Our continuous problem is cast as a multiple traces time-domain boundary integral formulation valid in two and three dimensions. Numerically, our two-dimensional non-conforming spatial discretization uses spectral elements based on second kind Chebyshev polynomials while a convolution quadrature scheme is performed in the complex frequency domain. Computational experiments reveal multistep and multistage convolution quadrature expected convergence results for a variety of complex domains.

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Carlos Jerez-Hanckes, Ignacio Labarca. 2020-11-15. Time-Domain Multiple Traces Boundary Integral Formulation for Acoustic Wave Scattering in 2D. https://arxiv.org/abs/2011.07434

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