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arXiv · 1407.1198

Asymptotic-preserving methods for an anisotropic model of electrical potential in a tokamak

Philippe Angot·Thomas Auphan·Olivier Guès
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Abstract

A 2D nonlinear model for the electrical potential in the edge plasma in a tokamak generates a stiff problem due to the low resistivity in the direction parallel to the magnetic field lines. An asymptotic-preserving method based on a micro-macro decomposition is studied in order to have a well-posed problem, even when the parallel resistivity goes to $0$. Numerical tests with a finite difference scheme show a bounded condition number for the linearised discrete problem solved at each time step, which confirms the theoretical analysis on the continuous problem.

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Philippe Angot, Thomas Auphan, Olivier Guès. 2014-07-04. Asymptotic-preserving methods for an anisotropic model of electrical potential in a tokamak. https://doi.org/10.1007/978-3-319-05591-6_46

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