Simulation of power exhaust in edge and divertor of the SlimCS tokamak demo reactor

Design of the power handling for the demo tokamak reactor, SlimCS, with the fusion power of Pfus ≤ 3 GW and the exhausted power of Pout=500 MW was investigated. First, effects of the divertor geometry of the V-shaped corner and the Ar impurity seeding on the radiation distribution and the target power loading were summarized in the simulation (SOLDOR/NEUT2D) with a constant concentration of Ar ions. Second, influence of the intense Ar impurity seeding was investigated in SONIC code, using Monte Carlo calculation (IMPMC). In this work, Ar transport and plasma evolution were self-consistently simulated up to a typical transport time in the divertor (t=30 ms). Results showed that Ar density and its concentration were significantly increased and their peaks were rather localized near the target. Influence of both ne and nAr enhancement on the peak power loading was significant in the full detached divertor, where qtarget=18 MW/m2 was attributed to the radiation power and was two times larger than the previous work. Further calculation up to a quasi-steady-state is necessary to obtain impurity and radiation distributions at the upstream of the divertor, SOL and edge. (author)