We consider the displacement of an electronic cloud generated by the local difference of charge with a uniform neutralizing background of non-moving ions. The equations are given by the Vlasov-Poisson system, with a coupling constant where τ is the (constant) oscillation period of the electrons. In the so-called quasi-neutral regime, namely as 0, the current is expected to converge to a solution of the incompressible Euler equations, at least in the case of a vanishing initial temperature. This result is proved by adapting an argument used by P.-L. Lions [Li] to prove the convergence of the Leray solutions of the 3d Navier-Stokes equation to the so-called dissipativesolutions of the Euler equations. For this purpose, the total energy of the system is modulated by a test-function. An alternative proof is given, based on the concept of measure-valued (mv) solutions introduced by DiPerna and Majda [DM] and already used by Brenier and Grenier [BG], [Gr2] for the asymptotic analysis of the Vlasov-Poisson system in the quasi-neutral regime. Through this analysis, a link is established between Lions' dissipative solutions and Diperna-Majda's (mv)solutions of the Euler equations. A second interesting asymptotic regime, still leading to the Euler equations, known as the gyrokinetic limit of the Vlasov-Poisson system, is obtained when the electrons are forced by a strong constant external magnetic field and has been investigated in [Gr3], [GSR]. As for the quasi-neutral limit, we jus- tify the gyrokinetic limit by using the concepts of dissipative solutions and modulated total energy.
[1]
Pierre-Louis Lions,et al.
Propagation of moments and regularity for the 3-dimensional Vlasov-Poisson system
,
1991
.
[2]
K. Pfaffelmoser,et al.
Global classical solutions of the Vlasov-Poisson system in three dimensions for general initial data
,
1992
.
[3]
Y. Brenier,et al.
Limite singulière du système de Vlasov-Poisson dans le régime de quasi neutralité : le cas indépendant du temps
,
1994
.
[4]
A. Majda,et al.
Oscillations and concentrations in weak solutions of the incompressible fluid equations
,
1987
.
[5]
J. Delort.
Existence de nappes de tourbillon en dimension deux
,
1991
.
[6]
Emmanuel Grenier,et al.
Defect measures of the vlasov-poisson system in the quasineutral regime
,
1995
.
[7]
V. Arnold,et al.
Topological methods in hydrodynamics
,
1998
.
[8]
F. Golse,et al.
L'approximation centre-guide pour l'équation de Vlasov-Poisson 2D
,
1998
.
[9]
P. Lions.
Mathematical topics in fluid mechanics
,
1996
.
[10]
J. Chemin,et al.
Fluides parfaits incompressibles
,
2018,
Astérisque.
[11]
Emmanuel Grenier.
Oscillations in quasineutral plasmas
,
1996
.
[12]
Mario Pulvirenti,et al.
Mathematical Theory of Incompressible Nonviscous Fluids
,
1993
.
[13]
E. Grenier.
Pseudo-differential energy estimates of singular perturbations
,
1997
.