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| Content Provider | Springer Nature Link |
|---|---|
| Author | Minkoff, Susan E. Lai, Chen |
| Copyright Year | 2017 |
| Abstract | Acoustic imaging and sensor modeling are processes that require repeated solution of the acoustic wave equation. Solution of the wave equation can be computationally expensive and memory intensive for large simulation domains. One scheme for speeding up solution of the wave equation is the operator-based upscaling method. The algorithm proceeds in two steps. First, the wave equation is solved for fine grid unknowns internal to coarse blocks assuming the coarse blocks do not need to communicate with neighboring blocks in parallel. Second, these fine grid solutions are used to form a new problem which is solved on the coarse grid. Accurate and efficient wave propagation schemes also must avoid artificial reflections off of the computational domain edges. One popular method for preventing artificial reflections is the nearly perfectly matched layer (NPML) method. In this paper, we discuss applying NPML to operator upscaling for the wave equation. We show that although we only apply NPML to the first step of this two step algorithm (directly affecting the fine grid unknowns only), we still see a significant reduction of reflections back into the domain. We describe three numerical experiments (one homogeneous medium experiment and two heterogeneous media examples) in which we validate that the solution of the wave equation exponentially decays in the NPML regions. Numerical experiments of acoustic wave propagation in two dimensions with a reasonable absorbing layer thickness resulted in a maximum pressure reflection of 3–8%. While the coarse grid acceleration is not explicitly damped in our algorithm, the tight coupling between the two steps of the algorithm results in only 0.1–1% of acceleration reflecting back into the computational domain. |
| Ending Page | 372 |
| Page Count | 14 |
| Starting Page | 359 |
| File Format | |
| ISSN | 14200597 |
| e-ISSN | 15731499 |
| Journal | Computational Geosciences |
| Issue Number | 3 |
| Volume Number | 21 |
| Language | English |
| Publisher | Springer International Publishing |
| Publisher Date | 2017-01-28 |
| Publisher Place | Cham |
| Access Restriction | One Nation One Subscription (ONOS) |
| Subject Keyword | Wave equation Nearly perfectly matched layers Acoustic wave propagation Earth Sciences Hydrogeology Absorbing boundary conditions Geotechnical Engineering & Applied Earth Sciences Mathematical Modeling and Industrial Mathematics Finite elements, Rayleigh-Ritz and Galerkin methods, finite methods Upscaling Finite difference methods Soil Science & Conservation |
| Content Type | Text |
| Resource Type | Article |
| Subject | Computers in Earth Sciences Computational Theory and Mathematics Computer Science Applications Computational Mathematics |
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