Variational Symplectic Integrator for Long-Time Simulations of the Guiding-Center Motion of Charged Particles in General Magnetic Fields

H. Qin and X. Guan

关键词: CHARGED PARTICLES;    DIFFERENTIAL EQUATIONS;    LAGRANGIAN FUNCTION;    MAGNETIC FIELDS;    RUNGE-KUTTA METHOD;    SIMULATION Gyrokinetic Equations;    Guiding-center Approximations;    Numerical Methods;    Numerical Simulation;   

DOI  :  10.2172/960290
RP-ID  :  PPPL-4286
PID  :  OSTI ID: 960290
Others  :  TRN: US0904420

学科分类：原子、分子光学和等离子物理

美国|英语

来源: SciTech Connect

【 摘 要 】

A variational symplectic integrator for the guiding-center motion of charged particles in general magnetic fields is developed for long-time simulation studies of magnetized plasmas. Instead of discretizing the differential equations of the guiding-center motion, the action of the guiding-center motion is discretized and minimized to obtain the iteration rules for advancing the dynamics. The variational symplectic integrator conserves exactly a discrete Lagrangian symplectic structure, and has better numerical properties over long integration time, compared with standard integrators, such as the standard and variable time-step fourth order Runge-Kutta methods.