Edge-localized-modes (ELMs) suppression by non-axisymmetric resonant-magnetic-perturbation (RMP) provides the way to reach high performance fusion plasmas without a threatening level of transient heat fluxes to the walls of fusion devices. The application of RMP, however, strongly modifies the heat flux pattern onto in-vessel components in contact with the plasma (especially the divertor) leading to local 'hot spots'. Radiative dissipation by partially ionized species (impurities and deuterium) lowers the heat flux peaks on the walls but has been poorly compatible with such RMP-driven, ELM-crash-suppression. Here, we show how KSTAR has radiatively tamed divertor thermal loading down to more than a factor of 7 in the off-separatrix region without losing ELM-crash-suppression using ITER-like, three-row, RMP configurations, demonstrating its sustainment even in a partially detached plasma in the outer strike point, as required for ITER.
This paper shows how the KSTAR fusion device has successfully reduced the intense heat flux on the divertor walls caused by edge-localized modes (ELMs) suppression using resonant magnetic perturbation (RMP). By using radiative cooling from partially ionized impurities and deuterium, the heat flux peaks were reduced by more than a factor of 7 without losing the ELM-crash-suppression, even in a partially detached plasma.