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arXiv · 1612.04127

An IMEX-RK scheme for capturing similarity solutions in the multidimensional Burgers' equation

Abstract

In this paper we introduce a new, simple and efficient numerical scheme for the implementation of the freezing method for capturing similarity solutions in partial differential equations. The scheme is based on an IMEX-Runge-Kutta approach for a method of lines (semi-)discretization of the freezing partial differential algebraic equation (PDAE). We prove second order convergence for the time discretization at smooth solutions in the ODE-sense and we present numerical experiments that show second order convergence for the full discretization of the PDAE. As an example serves the multi-dimensional Burgers' equation. By considering very different sizes of viscosity, Burgers' equation can be considered as a prototypical example of general coupled hyperbolic-parabolic PDEs. Numerical experiments show that our method works perfectly well for all sizes of viscosity, suggesting that the scheme is indeed suitable for capturing similarity solutions in general hyperbolic-parabolic PDEs by direct forward simulation with the freezing method.

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BibTeXRIS

Jens Rottmann-Matthes. 2016-12-13. An IMEX-RK scheme for capturing similarity solutions in the multidimensional Burgers' equation. https://arxiv.org/abs/1612.04127

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