A staggered-grid finite-difference scheme optimized in the time-space domain for modeling scalar-wave propagation in geophysical problems

JOURNAL OF COMPUTATIONAL PHYSICS

卷:276

Article

Tan, Sirui¹  Huang, Lianjie² 

[1] Formerly Alamos Natl Lab, Geophys Grp, Los Alamos, NM 87545 USA

[2] Los Alamos Natl Lab, Geophys Grp, Los Alamos, NM 87545 USA

关键词: Dispersion error;    Finite-difference scheme;    Finite-difference stencil;    Numerical modeling;    Optimized scheme;    Scalar wave;    Wave propagation;   

DOI  :  10.1016/j.jcp.2014.07.044

来源: Elsevier

【 摘 要 】

For modeling scalar-wave propagation in geophysical problems using finite-difference schemes, optimizing the coefficients of the finite-difference operators can reduce numerical dispersion. Most optimized finite-difference schemes for modeling seismic-wave propagation suppress only spatial but not temporal dispersion errors. We develop a novel optimized finite-difference scheme for numerical scalar-wave modeling to control dispersion errors not only in space but also in time. Our optimized scheme is based on a new stencil that contains a few more grid points than the standard stencil. We design an objective function for minimizing relative errors of phase velocities of waves propagating in all directions within a given range of wavenumbers. Dispersion analysis and numerical examples demonstrate that our optimized finite-difference scheme is computationally up to 2.5 times faster than the optimized schemes using the standard stencil to achieve the similar modeling accuracy for a given 2D or 3D problem. Compared with the high-order finite-difference scheme using the same new stencil, our optimized scheme reduces 50 percent of the computational cost to achieve the similar modeling accuracy. This new optimized finite-difference scheme is particularly useful for large-scale 3D scalar-wave modeling and inversion. Published by Elsevier Inc.

【 授权许可】

Free