An Ingenious Plasma Simulation Model for Large-Scale System with Self-Consistent Electron Dynamics

Abstract

An ingenious model for large-scale plasma simulations is proposed. An artificial permittivity ε_∗ much grater than ε₀ (permittivity of free space) is introduced to the Poisson equation, ∇· (ε_∗∇φ) = −ρ (φ is electrostatic potential and ρ is charge density), and the Debye length is artificially elongated. A large-scale system with a reasonable number of spatial grids can be treated stably even for including the self-consistent electron dynamics. A dielectric tensor is adopted for the three-dimensional global simulation of tokamak plasmas in the cylindrical coordinates (R, θ, Z). A diagonal element ε_θθ for toroidal axis θ is set much larger than those for the poloidal plane, ε_RR = ε_ZZ = ε_∗. Number of toroidal meshes N_θ can be reduced enough smaller than that of poloidal-plane meshes, N_R and N_Z, in comparison with N_θ > N_R, N_Z for the usual case of isotropic ε_∗.