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arXiv · 1608.08326

Optimal damping ratios of multi-axial perfectly matched layers for elastic-wave modeling in general anisotropic media

Kai Gao·Lianjie Huang
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Abstract

The conventional Perfectly Matched Layer (PML) is unstable for certain kinds of anisotropic media. This instability is intrinsic and independent of PML formulation or implementation. The Multi-axial PML (MPML) removes such instability using a nonzero damping coefficient in the direction parallel with the interface between a PML and the investigated domain. The damping ratio of MPML is the ratio between the damping coefficients along the directions parallel with and perpendicular to the interface between a PML and the investigated domain. No quantitative approach is available for obtaining these damping ratios for general anisotropic media. We develop a quantitative approach to determining optimal damping ratios to not only stabilize PMLs, but also minimize the artificial reflections from MPMLs. Numerical tests based on finite-difference method show that our new method can effectively provide a set of optimal MPML damping ratios for elastic-wave propagation in 2D and 3D general anisotropic media.

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BibTeXRIS

Kai Gao, Lianjie Huang. 2016-08-30. Optimal damping ratios of multi-axial perfectly matched layers for elastic-wave modeling in general anisotropic media. https://arxiv.org/abs/1608.08326

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