Nonlinear gyrokinetic equations

Nonlinear relativistic gyrokinetic Vlasov-Maxwell equations

A set of self-consistent nonlinear gyrokinetic equations is derived for relativistic charged particles in a general nonuniform magnetized plasma. Full electromagnetic-field fluctuations are considered with spatial and temporal scales given by the low-frequency gyrokinetic ordering. Self-consistency is obtained by combining the nonlinear relativistic gyrokinetic Vlasov equation with the low-freq...

Fully electromagnetic nonlinear gyrokinetic equations for tokamak edge turbulence

Nonlinear electromagnetic gyrokinetic simulations of tokamak plasmas

One of the central physics issues currently targeted by nonlinear gyrokinetic simulations is the role of finite-β effects. The latter change the MHD equilibrium, introduce new dynamical space and time scales, alter and enlarge the zoo of electrostatic microinstabilities and saturation mechanisms, and lead to turbulent transport along fluctuating magnetic field lines. It is shown that the electr...

Nonlinear quasi-steady state benchmark of global gyrokinetic codes

Two global gyrokinetic codes are benchmarked against each other by comparing simulation results in the case of ion temperature gradient driven (ITG) turbulence, in the adiabatic electron response limit. The two codes are the Eulerian code GENE and the Lagrangian Particle-In-Cell code ORB5 which solve the gyrokinetic equations. Linear results are presented, including growth rates, real frequenci...

Towards optimal explicit time-stepping schemes for the gyrokinetic equations

The nonlinear gyrokinetic equations describe plasma turbulence in laboratory and astrophysical plasmas. To solve these equations, massively parallel codes are developed and run on present-day supercomputers. The goal of this paper is to improve the efficiency of such computations, thereby allowing for physically more comprehensive studies. Explicit Runge-Kutta schemes are considered to be well ...