Higham, D.J. and Owren, B.
(1996)
*Non-normality effects in a discretised, nonlinear, reaction-convection-diffusion equation.*
Journal of Computational Physics, 124 (2).
pp. 309-323.
ISSN 0021-9991

## Abstract

What is the long-time effect of adding convention to a discretised reaction-diffusion equation? For linear problems, it is well known that convection may denormalise the process, and, in particular, eigenvalue-based stability predictions may be overoptimistic. This work deals with a related issue - with a nonlinear reaction term, the nonnormality can greatly influence the long-time dynamics. For a nonlinear model problem with Dirichlet boundary conditions, it is shown that the basin of attraction of the 'correct' steady state can be shrunk in a directionally biased manner. A normwise analysis provides lower bounds on the basin of attraction and a more revealing picture is provided by pseudo-eigenvalues. In extreme cases, the computed solution can converge to a spurious, bounded, steady state that exists only in finite precision arithmetic. The impact of convection on the existence and stability of spurious, periodic solutions is also quantified.

Item type: | Article |
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ID code: | 192 |

Keywords: | discretised reaction-diffusion equation, linear problems, differential equations, mathematics, Dirichlet boundary, convection, Mathematics, Physics and Astronomy (miscellaneous), Computer Science Applications |

Subjects: | Science > Mathematics |

Department: | Faculty of Science > Mathematics and Statistics |

Depositing user: | Ms Sarah Scott |

Date Deposited: | 01 Mar 2006 |

Last modified: | 20 Oct 2015 10:53 |

URI: | http://strathprints.strath.ac.uk/id/eprint/192 |

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