Plasma Simulation and Surface Effects in a High-Field Tokamak Ignition Experiment

Plasma loading of the wall and limiter surfaces will play an important part in ignited tokamak experiments. Fusion plasmas will be characterized by high edge temperatures and large radially outward particle and energy fluxes. Many aspects of plasma-surface interactions presently seen in tokamak experiments will change and altogether new phenomena may appear. In this paper we identify possible plasma-surface interactions in a tokamak ignition experiment which can significantly affect its operation. The proposed ignition experiment, IGNITEX, is considered. The IGNITEX experiment will use a single-turn coil to produce a 20 Tesla toroidal field in a compact tokamak. A deuteriumtritium plasma will be gas fueled and ohmically heated to ignition. To obtain detailed edge plasma profiles and fluxes, a 1-D transport code is utilized. Ion and charge-exchange neutral sputtering processes at an all carbon surface system are included. A detailed description of the radial particle and energy flux calculations is given.