The influence of cross field diffusion and convection on the impurity ion transport in the limiter shadow region of a tokamak 2: Some numerical results

The analytical results presented in ref, [1] concerning the metal impurity transport in radially homogeneous plasma zones (1$\overrightarrow{B}$) have been numerically evaluated in two cases : (a) steady-state impurity distribution around a plane target immersed into a plasma flow along the magnetic field with uniform plasma parameters $\bot \overrightarrow{B}$ , (b) time evolution of an impurity pulse injected into the plasma flow at an upstream source point. Due to their relative simplicity the results could be discussed in some detail and the underlying physical phenomena elucidated. As limiting cases of more realistic and therefore more complicated situations (including radial gradients of the plasma parameters, thermalization between impurity and hydrogen ions as well as recombination processes) they may serve as benchmarks to check more general Monte-Carlo calculations