Plasma Simulation Using Gyrokinetic-Gyrofluid Hybrid Models

Scott Parker

关键词: ALPHA PARTICLES;    CYCLOTRONS;    DAMPING;    ELECTRONS;    KINETICS;    LORENTZ FORCE;    MAGNETIC RECONNECTION;    MAGNETOHYDRODYNAMICS;    PHYSICS;    PLASMA;    SHEAR;    SIMULATION;    TURBULENCE;   

DOI  :  10.2172/1010522
RP-ID  :  DOE/04ER54800-1 Final Report
PID  :  OSTI ID: 1010522
Others  :  TRN: US1102306

学科分类：核物理和高能物理

美国|英语

来源: SciTech Connect

【 摘 要 】

We are developing kinetic ion models for the simulation of extended MHD phenomena. The model they have developed uses full Lorentz force ions, and either drift-kinetic or gyro-kinetic electrons. Quasi-neutrality is assumed and the displacement current is neglected. They are also studying alpha particle driven Toroidal Alfven Eigenmodes (TAE) in the GEM gyrokinetic code [Chen 07]. The basic kinetic ion MHD model was recently reported in an invited talk given by Dan Barnes at the 2007 American Physical Society - Division of Plasma Physics (APS-DPP) and it has been published [Jones 04, Barnes 08]. The model uses an Ohm's law that includes the Hall term, pressure term and the electron inertia [Jones 04]. These results focused on the ion physics and assumed an isothermal electron closure. It is found in conventional gyrokinetic turbulence simulations that the timestep cannot be made much greater than the ion cyclotron period. However, the kinetic ion MHD model has the compressional mode, which further limits the timestep. They have developed an implicit scheme to avoid this timestep constraint. They have also added drift kinetic electrons. This model has been benchmarked linearly. Waves investigated where shear and compressional Alfven, whisterl, ion acoustic, and drift waves, including the kinetic damping rates. This work is ongoing and was first reported at the 2008 Sherwood Fusion Theory Conference [Chen 08] and they are working on a publication. They have also formulated an integrated gyrokinetic electron model, which is of interest for studying electron gradient instabilities and weak guide-field magnetic reconnection.