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arXiv · 1104.3339

Asymptotic-Preserving scheme for a bi-fluid Euler-Lorentz model

Stéphane Brull·Pierre Degond·Fabrice Deluzet·Alexandre Mouton
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Abstract

The present work is devoted to the simulation of a strongly magnetized plasma considered as a mixture of an ion fluid and an electron fluid. For the sake of simplicity, we assume that the model is isothermal and described by Euler equations coupled with a term representing the Lorentz force. Moreover we assume that both Euler systems are coupled through a quasi-neutrality constraint. The numerical method which is described in the present document is based on an Asymptotic-Preserving semi-discretization in time of a variant of this two-fluid Euler-Lorentz model with a small perturbation of the quasi-neutrality constraint. Firstly, we present the two-fluid model and the motivations for introducing a small perturbation into the quasi-neutrality equation, then we describe the time semi-discretization of the perturbed model and a fully-discrete finite volume scheme based on it. Finally, we present some numerical results which have been obtained with this method.

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Stéphane Brull, Pierre Degond, Fabrice Deluzet, Alexandre Mouton. 2011-04-17. Asymptotic-Preserving scheme for a bi-fluid Euler-Lorentz model. https://doi.org/10.3934/krm.2011.4.991

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