Perpendicular Conductivity and Self-Consistent Electric Fields in Small Size Divertor Tokamak Plasma Edge

摘要

The radial electric field of small size divertor tokamak in the vicinity of separtrix is simulated by using B2-SOLPS5.0 2D code, in which the most complete system of transport equations (Rozhansky et al., Nucl Fusion, 41:4, 2001) is solved including all the important perpendicular current and E x B drifts. Simulations demonstrated the following results: (a) It is shown that in the vicinity of the separatrix, the radial potential profile is determined by perpendicular currents (b) since, due to the pressure asymmetry, radial diamagnetic current integrated over the closed flux surface is not automatically zero, additional radial currents balance the diamagnetic current and make the average net current zero, (c) On the closed flux surfaces far from separetrix, where the pressure is almost constant, the calculated parallel currents (toroidal current) agree with Pfirsch-Schlueter currents.