Numerical Investigation of the Time Evolution of Impurity Concentration in a Tokamak

Numerical analysis has been made of the time evolution in density profiles of the impurities in a Tokamak. The diffusion and atomic processes of impurities are treated simultaneously. Two different numerical methods were used; the results are in good agreement between the two. Calculations are made in the case of a constant spatial distribution of the plasma. The impurity concentration in the plasma is revealed. The procedure may be useful for analysis of the time evolution of a Tokamak plasma in computer simulation and for the analysis of the impurities by optical measurement