Young Researchers Workshop: Stochastic and deterministic methods in kinetic theory


A uniformly efficient method for spatial inhomogeneous plasma

Bokai Yan

University of California, Los Angeles

Abstract:  

Long range Coulomb collisions between charged particles (electrons and ions) play a crucial role in nonequilibrium plasma. Particle based methods such as Particle-In-Cell (PIC) methods and DSMC methods are widely used in simulating these processes. However, these methods become highly inefficient as the system approaches equilibrium, because the major cost is spent on simulating the meaningless collisions in equilibrium. By incorporating a "deviational particle" based Monte Carlo method to simulate the deviation from equilibrium, we developed a uniformly efficient hybrid method for the spatial inhomogeneous plasma modeled by Vlasov-Poisson-Landau system. This method is applicable and efficient in all regimes. It achieves the efficiency of a fluid solver when the deviation is small; and it becomes a PIC-DSMC method when the deviation is large.