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arXiv · 2010.09307

Parameter-uniform approximations for a singularly perturbed convection-diffusion problem with a discontinuous initial condition

Jose Luis Gracia·Eugene O'Riordan
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Abstract

A singularly perturbed parabolic problem of convection-diffusion type with a discontinuous initial condition is examined. A particular complimentary error function is identified which matches the discontinuity in the initial condition. The difference between this analytical function and the solution of the parabolic problem is approximated numerically. A co-ordinate transformation is used so that a layer-adapted mesh can be aligned to the interior layer present in the solution. Numerical analysis is presented for the associated numerical method, which establishes that the numerical method is a parameter-uniform numerical method. Numerical results are presented to illustrate the pointwise error bounds established in the paper.

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Jose Luis Gracia, Eugene O'Riordan. 2020-10-19. Parameter-uniform approximations for a singularly perturbed convection-diffusion problem with a discontinuous initial condition. https://arxiv.org/abs/2010.09307

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