Evolution of the divertor configuration during a tokamak discharge

A 1-1/2 dimensional tokamak transport code TDTR able to optimize a divertor configuration has been developed. Evolution of the divertor configuration during a tokamak discharge (in the plateau phase of plasma current) is numerically studied using the code. Numerical simulations with different initial current profile, elongation, and triangularity in the cases of ohmic heating and auxiliary heating are implemented. It is shown that the position of the X-point has little change for an initial centrally flattened plasma current profile, but the divertor configuration can only be maintained for about 0.3-0.4 s in the case of a peaking current profile