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arXiv · 1703.03325

An adaptive finite element PML method for the acoustic-elastic interaction in three dimensions

Xue Jiang·Peijun Li
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Abstract

Consider the scattering of a time-harmonic acoustic incident wave by a bounded, penetrable, and isotropic elastic solid, which is immersed in a homogeneous compressible air or fluid. The paper concerns the numerical solution for such an acoustic-elastic interaction problem in three dimensions. An exact transparent boundary condition (TBC) is developed to reduce the problem equivalently into a boundary value problem in a bounded domain. The perfectly matched layer (PML) technique is adopted to truncate the unbounded physical domain into a bounded computational domain. The well-posedness and exponential convergence of the solution are established for the truncated PML problem by using a PML equivalent TBC. An a posteriori error estimate based adaptive finite element method is developed to solve the scattering problem. Numerical experiments are included to demonstrate the competitive behavior of the proposed method.

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Xue Jiang, Peijun Li. 2017-03-09. An adaptive finite element PML method for the acoustic-elastic interaction in three dimensions. https://arxiv.org/abs/1703.03325

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