Absorbing boundary conditions for time harmonic wave propagation in discretized domains

2011 ◽  
Vol 200 (33-36) ◽  
pp. 2483-2497 ◽  
Author(s):  
Senganal Thirunavukkarasu ◽  
Murthy N. Guddati
Keyword(s):  
Wave Propagation ◽  
Boundary Conditions ◽  
Harmonic Wave ◽  
Absorbing Boundary Conditions ◽  
Absorbing Boundary ◽  
Time Harmonic

scholarly journals Sweeping preconditioners for stratified media in the presence of reflections

2020 ◽  
Vol 1 (4) ◽  
Author(s):  
Janosch Preuß ◽  
Thorsten Hohage ◽  
Christoph Lehrenfeld
Keyword(s):  
Boundary Conditions ◽  
Harmonic Wave ◽  
Absorbing Boundary Conditions ◽  
Stratified Medium ◽  
Stratified Media ◽  
Absorbing Boundary ◽  
Small Perturbations ◽  
Numerical Tests ◽  
Time Harmonic ◽  
Dirichlet To Neumann Operator

Abstract In this paper we consider sweeping preconditioners for time harmonic wave propagation in stratified media, especially in the presence of reflections. In the most famous class of sweeping preconditioners Dirichlet-to-Neumann operators for half-space problems are approximated through absorbing boundary conditions. In the presence of reflections absorbing boundary conditions are not accurate resulting in an unsatisfactory performance of these sweeping preconditioners. We explore the potential of using more accurate Dirichlet-to-Neumann operators within the sweep. To this end, we make use of the separability of the equation for the background model. While this improves the accuracy of the Dirichlet-to-Neumann operator, we find both from numerical tests and analytical arguments that it is very sensitive to perturbations in the presence of reflections. This implies that even if accurate approximations to Dirichlet-to-Neumann operators can be devised for a stratified medium, sweeping preconditioners are limited to very small perturbations.

An optimal absorbing boundary condition for elastic wave modeling

Geophysics ◽  
1995 ◽  
Vol 60 (1) ◽  
pp. 296-301 ◽  
Author(s):  
Chengbin Peng ◽  
M. Nafi Toksöz
Keyword(s):  
Boundary Condition ◽  
Wave Propagation ◽  
Finite Difference ◽  
Boundary Conditions ◽  
Elastic Wave ◽  
Short Note ◽  
Absorbing Boundary Conditions ◽  
Parallel Computer ◽  
Absorbing Boundary Condition ◽  
Absorbing Boundary

Absorbing boundary conditions are widely used in numerical modeling of wave propagation in unbounded media to reduce reflections from artificial boundaries (Lindman, 1975; Clayton and Engquist, 1977; Reynolds, 1978; Liao et al., 1984; Cerjan et al., 1985; Randall, 1988; Higdon, 1991). We are interested in a particular absorbing boundary condition that has maximum absorbing ability with a minimum amount of computation and storage. This is practical for 3-D simulation of elastic wave propagation by a finite‐difference method. Peng and Toksöz (1994) developed a method to design a class of optimal absorbing boundary conditions for a given operator length. In this short note, we give a brief introduction to this technique, and we compare the optimal absorbing boundary conditions against those by Reynolds (1978) and Higdon (1991) using examples of 3-D elastic finite‐difference modeling on an nCUBE-2 parallel computer. In the Appendix, we also give explicit formulas for computing coefficients of the optimal absorbing boundary conditions.

Sign in / Sign up

Export Citation Format

Share Document