Topic
Finite difference method
About: Finite difference method is a research topic. Over the lifetime, 21603 publications have been published within this topic receiving 468852 citations. The topic is also known as: Finite-difference methods & FDM.
Papers published on a yearly basis
1 / 2
Papers
TL;DR: In this article, a vertical transversely isotropic wave system of equations that is equivalent to their elastic counterpart is derived and introduced to stabilize the TTI acoustic wave equations, and a stable solution can be found by either a pseudospectral method or a high-order explicit finite difference scheme.
Abstract: Modeling and reverse time migration based on the tilted transverse isotropic (TTI) acoustic wave equation suffers from instability in media of general inhomogeniety, especially in areas where the tilt abruptly changes. We develop a stable TTI acoustic wave equation implementation based on the original elastic anisotropic wave equation. We, specifically, derive a vertical transversely isotropic wave system of equations that is equivalent to their elastic counterpart and introduce the self-adjoint differential operators in rotated coordinates to stabilize the TTI acoustic wave equations. Compared to the conventional formulations, the new system of equations does not add numerical complexity; a stable solution can be found by either a pseudospectral method or a high-order explicit finite difference scheme. We demonstrate by examples that our method provides stable and high-quality TTI reverse time migration images.
239 citations
TL;DR: In this article, the energy conservation properties of a hydrostatic, Boussinesq, coastal ocean model using a classic finite difference method are investigated. But the authors do not consider the effect of the motion of the free surface on energy conservation.
238 citations
Book•
1 Jan 1977
TL;DR: In this paper, the origins of the first scheme were discussed and the second and third schemes were executed on the intermediate layer and the final layer, respectively, and the first and second schemes on the third and fourth layers, respectively.
Abstract: 1. General Introduction.- 1.1 Introduction.- 1.2 Boundary Value Problems and Initial Problems.- 1.3 One-Dimensional Unsteady Flow Characteristics.- 1.4 Steady Supersonic Plane or Axi-Symmetric Flow. Equations of Motion in Characteristic Form.- 1.5 Basic Concepts Used in Finite Difference Methods.- References.- 2. The Godunov Schemes.- 2.1 The Origins of Godunov's First Scheme.- 2.2 Godunov's First Scheme. One-Dimensional Eulerian Equations.- 2.3 Godunov's First Scheme in Two and More Dimensions.- 2.4 Godunov's Second Scheme.- 2.5 The Double Sweep Method.- 2.6 Execution of the Second Scheme on the Intermediate Layer.- 2.7 Boundary Conditions on the Intermediate Layer.- 2.8 Procedure on the Final Layer.- 2.9 Applications of the Second Godunov Scheme.- 2.10 Glimm's Method.- 2.11 Outline of Solution for Gas Dynamic Equations.- 2.12 The Glimm Scheme for Simple Acoustic Waves.- 2.13 Random Choice for the Gas Dynamic Equations.- 2.14 Solution of the Riemann Problem.- 2.15 Extension to Unsteady Flow with Cylindrical or Spherical Symmetry.- 2.16 Remarks on Multi-Dimensional Problems.- References.- 3. The BVLR Method.- 3.1 Description of Method for Supersonic Flow.- 3.2 Extensions to Mixed Subsonic-Supersonic Flow. The Blunt Body Problem.- 3.3 The Double Sweep Method for Unsteady Three-Dimensional Flow.- 3.4 Worked Problem. Application to Circular Arc Airfoil.- 3.5 Results and Discussion.- Appendix-Shock Expansion Theory.- References.- 4. The Method of Characteristics for Three-Dimensional Problems in Gas Dynamics.- 4.1 Introduction.- 4.2 Bicharacteristics Method (Butler).- 4.3 Optimal Characteristics Methods (Bruhn and Haack, Schaetz).- 4.4 Near Characteristics Method (Sauer).- References.- 5. The Method of Integral Relations.- 5.1 Introduction.- 5.2 General Formulation. Model Problem.- 5.3 Flow Past Ellipses.- 5.4 The Supersonic Blunt Body Problem.- 5.5 Transonic Flow.- 5.6 Incompressible Laminar Boundary Layer Equations. Basic Formulation.- 5.7 The Method in the Compressible Case.- 5.8 Laminar Boundary Layers with Suction or Injection.- 5.9 Extension to Separated Flows.- 5.10 Application to Supersonic Wakes and Base Flows.- 5.11 Application to Three-Dimensional Laminar Boundary Layers.- 5.12 A Modified Form of the Method of Integral Relations.- 5.13 Application to Viscous Supersonic Conical Flows.- 5.14 Extension to Unsteady Laminar Boundary Layers.- 5.15 Application to Internal Flow Problems.- Model Problem (Chu and Gong).- References.- 6. Telenin's Method and the Method of Lines.- 6.1 Introduction.- 6.2 Solution of Laplace's Equation by Telenin's Method.- 6.3 Solution of a Model Mixed Type Equation by Telenin's Method.- 6.4 Application of Telenin's Method to the Symmetrical Blunt Body Problem.- 6.5 Extension to Unsymmetrical Blunt Body Flows.- 6.6 Application of Telenin's Method to the Supersonic Yawed Cone Problem.- 6.7 The Method of Lines. General Description.- 6.8 Applications of the Method of Lines.- 6.9 Powell's Method Applied to Two Point Boundary Value Problems.- Telenin's Method. Model Problems (Klopfer).- References.
238 citations
TL;DR: It is demonstrated, using asymptotic expansions, that the error can be bounded very precisely indeed at the cost of few extra derivative evaluations, and in place of derivatives it is possible to use finite difference approximations, which renders the computation of error bounds even cheaper.
Abstract: The main theme of this paper is the construction of efficient, reliable and affordable error bounds for two families of quadrature methods for highly oscillatory integrals. We demonstrate, using asymptotic expansions, that the error can be bounded very precisely indeed at the cost of few extra derivative evaluations. Moreover, in place of derivatives it is possible to use finite difference approximations, with spacing inversely proportional to frequency. This renders the computation of error bounds even cheaper and, more importantly, leads to a new family of quadrature methods for highly oscillatory integrals that can attain arbitrarily high asymptotic order without computation of derivatives.
237 citations
TL;DR: In this article, a finite-difference scheme for the electromagnetic field in 3D anisotropic media for electromagnetic logging was proposed, which has the following features: coercivity (i.e., the complete discrete analogy of all continuous equations in every grid cell, even for nondiagonal conductivity tensors), a special conductivity averaging, and a spectrally optimal grid refinement minimizing the error at the receiver locations and optimizing the approximation of the boundary conditions at infinity.
Abstract: We consider a problem of computing the electromagnetic field in 3D anisotropic media for electromagnetic logging. The proposed finite-difference scheme for Maxwell equations has the following new features based on some recent and not so recent developments in numerical analysis: coercivity (i.e., the complete discrete analogy of all continuous equations in every grid cell, even for nondiagonal conductivity tensors), a special conductivity averaging that does not require the grid to be small compared to layering or fractures, and a spectrally optimal grid refinement minimizing the error at the receiver locations and optimizing the approximation of the boundary conditions at infinity. All of these features significantly reduce the grid size and accelerate the computation of electromagnetic logs in 3D geometries without sacrificing accuracy.
236 citations
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Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 53 |
| 2024 | 136 |
| 2023 | 170 |
| 2022 | 357 |
| 2021 | 733 |
| 2020 | 690 |