The ITER divertor

The ITER divertor design is based on the high density exhaust concept of reducing peak heat fluxes falling on the divertor plates. The power is transferred from the edge plasma to the walls of the divertor chamber by atomic and molecular processes such as radiation, charge exchange, recombination, and gas conduction before it can reach tile divertor plates. Although the feasibility of this concept for ITER has not yet been fully established, experiments in present day tokamaks show that such a configuration can be sustained and preliminary results indicate that the present concept is promising, even for the very demanding power levels of ITER. Simulation codes are not yet complete and more progress in modelling high density, high power experiments is still needed. Model development and validation continues to be one of the main efforts in the development of the ITER divertor concept, in particular on modelling the implication of transients on the divertor. This paper summarises the ITER divertor concept, discusses the state of supporting experiments and models and focuses on design requirements approaches.