Approximate local Dirichlet-to-Neumann map for three-dimensional time-harmonic elastic waves

作者：Chaillat Stephanie; Darbas Marion^*; Le Louer Frederique

来源：Computer Methods in Applied Mechanics and Engineering, 2015, 297: 62-83.

DOI：10.1016/j.cma.2015.08.013

• Scattering
• Time-harmonic elastic waves
• Approximate local DtN map
• Far-field patterns

It has been proven that the knowledge of an accurate approximation of the Dirichlet-to-Neumann (DtN) map is useful for a large range of applications in wave scattering problems. We are concerned in this paper with the construction of an approximate local DtN operator for time-harmonic elastic waves. The main contributions are the following. First, we derive exact operators using Fourier analysis in the case of an elastic half-space. These results are then extended to a general three-dimensional smooth closed surface by using a local tangent plane approximation. Next, a regularization step improves the accuracy of the approximate DtN operators and a localization process is proposed. Finally, a first application is presented in the context of the On-Surface Radiation Conditions method. The efficiency of the approach is investigated for various obstacle geometries at high frequencies.

• 出版日期2015-12-1
• 单位INRIA