Hauray, M.; Nouri, A.
Well-posedness of a diffusive gyro-kinetic model
Annales de l'I.H.P. Analyse non linéaire, Tome 28 (2011) no. 4 , p. 529-550
Zbl 1269.82075 | MR 2823883 | 2 citations dans Numdam
doi : 10.1016/j.anihpc.2011.03.002
URL stable : http://www.numdam.org/item?id=AIHPC_2011__28_4_529_0

Classification:  41A60,  76P05,  82A70,  78A35
On étudie un modèle à rayon de Larmor fini décrivant la fonction de distribution des ions dans un plasma de coeur de tokamak. Il consiste en une équation de transport gyrocinétique couplée à une équation de quasi-neutralité. Lʼéquation de quasi-neutralité donnant peu de régularité au potentiel électrique, on introduit un opérateur de collisions linéaire adapté. On étudie alors la dynamique du système dans la direction perpendiculaire au champ magnétique. Lʼeffet régularisant des opérateurs de collisions et de gyro-moyenne permet de démontrer lʼexistence globale de solutions ainsi que leur unicité et stabilité locales en temps.
We study a finite Larmor radius model used to describe the ions distribution function in the core of a tokamak plasma, that consists in a gyro-kinetic transport equation coupled with an electro-neutrality equation. Since the last equation does not provide enough regularity on the electric potential, we introduce a simple linear collision operator adapted to the finite Larmor radius approximation. We next study the two-dimensional dynamics in the direction perpendicular to the magnetic field. Thanks to the smoothing effects of the collision and the gyro-average operators, we prove the global existence of solutions, as well as short time uniqueness and stability.

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