Gyrokinetic particle simulation model
A new type of particle simulation model based on the gyrophase-averaged Vlasov and Poisson equations is presented. The reduced system in which particle gyrations are removed from the equations of motion while the finite Larmor radius effects are still preserved, is most suitable for studying low frequency microinstabilities in magnetized plasmas. The resulting gyrokinetic plasma is intrinsically quasineutral for \(\lambda_ D\ll \rho_ s\). Thus, without the troublesome space charge waves in the simulation, we can afford to use much larger time steps and grid spacings at a much reduced noise level than we would have for conventional particle codes. Furthermore, it is feasible to simulate an elongated system with a three-dimensional grid using the present model without resorting to the usual mode expansion technique, since there is essentially no restriction on the size of \(\Delta x_{\|}\) in a gyrokinetic plasma. The new approach also enables us to further separate the time and spatial scales of the simulation from those associated with global transport through the use of multiple spatial scale expansion. Thus, the model can be a very efficient tool for studying anomalous transport problems related to steady-state drift-wave turbulence in magnetic confinement devices. It can also be applied to other areas of plasma physics.
gyrophase-averaged Vlasov-Poisson system
scientific article; zbMATH DE number 4005861
scientific article