Fluid simulations of conducting‐wall‐driven turbulence in boundary plasmas

It is clear that the edge plasma plays a crucial role in global tokamak confinement. This paper is a report on simulations of a new drift wave type instability driven by conducting wall (also originally named as a ∇Te instability) [Phys. Fluids B 3, 1364 (1991)]. A 2d(x,y) fluid code has been developed in order to explore the anomalous transport in the boundary plasmas. The simulation consists of a set of fluid equations (in the electrostatic limit) for the vorticity ∇⊥2φ, and the temperature Te in a shearless plasma slab confined by a uniform, straight magnetic field Bz with two divertor (or limiter) plates intercepting the magnetic field. The model has two regions separated by a magnetic separatrix: In the edge region inside the separatrix, the model is periodic along the magnetic field while in the scrapeoff layer (SOL) region outside the separatrix, the magnetic field is taken to be of finite length with model (logical sheath) boundary conditions at diverter (or limiter) plates. The simulation results...