High frequency elastic wave propagation in large structures using spectral elements and perfectly matched layer

2014 ◽  
Author(s):  
Zahra Heidary ◽  
Didem Ozevin
2010 ◽  
Author(s):  
B. Tie ◽  
D. Aubry ◽  
A.-S. Mouronval ◽  
D. Solas ◽  
J. Thébault ◽  
...  

2016 ◽  
Vol 22 (1) ◽  
pp. 20-37 ◽  
Author(s):  
Hisham Assi ◽  
Richard S. Cobbold

A new second-order formulation is obtained for elastic wave propagation in 2D media bounded by a perfectly matched layer (PML). The formulation uses a complex coordinate stretching approach with a two-parameter stretch function. The final system, consisting of just two second-order displacement equations along with four auxiliary equations, is smaller than existing formulations, thereby simplifying the problem and reducing the computational cost. With the help of a plane-wave analysis, the stability of the continuous formulation is examined. It is shown that by increasing the scaling parameter in the stretch function, any existing instability is moved to higher spatial frequencies. Since discrete models cannot resolve frequencies beyond a certain limit, this can lead to significant computational stability improvements. Numerical results are shown to validate our formulation and to illustrate the improved stability that can be achieved with certain anisotropic media that have known issues.


Geophysics ◽  
2003 ◽  
Vol 68 (5) ◽  
pp. 1749-1755 ◽  
Author(s):  
Tsili Wang ◽  
Xiaoming Tang

In this paper, we present a nonsplitting perfectly matched layer (NPML) method for the finite‐difference simulation of elastic wave propagation. Compared to the conventional split‐field approach, the new formulation solves the same set of equations for the boundary and interior regions. The nonsplitting formulation simplifies the perfectly matched layer (PML) algorithm without sacrificing the accuracy of the PML. In addition, the NPML requires nearly the same amount of computer storage as does the split‐field approach. Using the NPML, we calculate dipole and quadrupole waveforms in a logging‐while‐drilling environment. We show that a dipole source produces a strong pipe flexural wave that distorts the formation arrivals of interest. A quadrupole source, however, produces clean formation arrivals. This result indicates that a quadrupole source is more advantageous over a dipole source for shear velocity measurement while drilling.


Sign in / Sign up

Export Citation Format

Share Document