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P: Plasmaphysik
P 12: Basic Plasma Physics, Theory
P 12.1: Vortrag
Mittwoch, 19. März 2003, 11:30–11:50, FO2
Investigation on plasma transport via particle simulation — •Dirk Naujoks — Max-Planck-Institut-für Plasmaphysik, EUROATOM Association, Bereich Plasmadiagnostik, Mohrenstr. 41, 10117 Berlin
The behavior of magnetized plasmas concerning charge shielding, ion confinement and electron transport has been investigated by means of the PIC (particle-in-cell)-code PLAS [1,2]. It is shown that the dimensionless ratio χ=npl m /(εo B2) being the dielectric susceptibility (with the plasma density npl, the mass m and the magnetic field strength B) is the main parameter in the analysis.
Starting with a thermal plasma (Te=Ti, imbedded in an external magnetic field) the evolution in time has been followed in a 2D modelling. In plasma regions with an ion pressure gradient an electric field arises which drives a drift motion of the electrons. Due to the Kelvin-Helmholtz instability this drift motion becomes unstable. A large number of interacting vortices with different rotation directions occur which lead to large electron transport across the magnetic field. This transport mechanism does not depend on the plasma density, but is proportional to the ratio of Ti/B. The capability of PIC-simulations and their main drawback: huge CPU-times requirements are discussed. A simplified plasma model (without collisions) is proposed to mitigate this problem.
[1] D. Naujoks, Contrib. Plasma Phys. 41 (2001) 375-386
[2] D. Naujoks, Contrib. Plasma Phys. 42 (2002) 356-361