The Large Discretization Step Method for Time-Dependent Partial Differential Equations.

Abstract

A new method for the acceleration of linear and nonlinear time dependent calculations is presented. It is based on the Large Discretization Step (LDS, in short) approximation, defined in this work, which employs an extended system of low accuracy schemes to approximate a high accuracy discrete approximation to a time dependent differential operator. Error bounds on such approximations are derived. These approximations are efficiently implemented in the LDS methods for linear and nonlinear hyperbolic equations, presented here. In these algorithms the high and low accuracy schemes are interpreted as the same discretization of a time dependent operator on fine and coarse grids, respectively. Thus, a system of correction terms and corresponding equations are derived and solved on the coarse grid to yield the fine grid accuracy. These terms are initialized by visiting the fine grid once in many coarse grid time steps. The resulting methods are very general, simple to implement and may be used to accelerate many existing time marching schemes. (AN)

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1995
Accession Number
ADA295663

Entities

People

  • Shlomo Ta'asan
  • Zigo Haras

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Algorithms
  • Computational Fluid Dynamics
  • Computational Science
  • Computations
  • Difference Equations
  • Differential Equations
  • Equations
  • Errors
  • Euler Equations
  • Fluid Mechanics
  • Fourier Analysis
  • Metal Matrix Composites
  • Partial Differential Equations
  • Simulations
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Computational Fluid Dynamics (CFD)
  • Fluid Dynamics.