Combining finite element and finite difference methods for isotropic elastic wave simulations in an energy-conserving manner

JOURNAL OF COMPUTATIONAL PHYSICS

卷:378

Article

Gao, Longfei¹  Keyes, David¹ 

[1] King Abdullah Univ Sci & Technol, Div Comp Elect & Math Sci & Engn, Thuwal 239556900, Saudi Arabia

关键词: Finite element method;    Finite difference method;    Interface treatment;    Elastic wave equation;    Discrete energy analysis;    Simultaneous approximation terms;   

DOI  :  10.1016/j.jcp.2018.11.031

来源: Elsevier

【 摘 要 】

We consider numerical simulation of the isotropic elastic wave equations arising from seismic applications with non-trivial land topography. The more flexible finite element method is applied to the shallow region of the simulation domain to account for the topography, and combined with the more efficient finite difference method that is applied to the deep region of the simulation domain. We demonstrate that these two discretization methods, albeit starting from different formulations of the elastic wave equation, can be joined together smoothly via weakly imposed interface conditions. Discrete energy analysis is employed to derive the proper interface treatment, leading to an overall discretization that is energy-conserving. Numerical examples are presented to demonstrate the efficacy of the proposed interface treatment. (C) 2018 Elsevier Inc. All rights reserved.

【 授权许可】

Free