Non-linear MHD Simulations of ELMs in a High Recycling Divertor

Guido Huijsmans (1, 2) , D C van Vugt (2) , S Franssen (2) , S Q Korving (2) , Marina Becoulet (1)

1 IRFM - Institut de Recherche sur la Fusion par confinement Magnétique
2 TU/e - Eindhoven University of Technology [Eindhoven]

ITER plasmas will be characterized by a high density plasma (i.e. Greenwald fraction) at low collisionality inside the separatrix, a high density in the scrape-off layer combined with a high recycling detached divertor. ELMs in ITER are expected to be tolerable at low plasma current but need to be controlled at the full 15MA current. Whether ELMs are tolerable depends in part on the interaction of the ELM energy and density losses with the detached divertor, i.e. do (very) small ELMs burn through the detached divertor plasma. Since the ITER regime cannot be obtained in current experiments, numerical simulations of ELMs are required for the extrapolation to ITER. Presently in the nonlinear MHD code JOREK, a fluid model is used to describe the main plasma and the neutrals. The time evolution of the neutrals is described by a diffusion model combined with a boundary condition which reflects outgoing ions as incoming neutrals. This fluid model has been successfully used to simulate ELMs in the super-X divertor of MAST-U [1] and is applied below to ITER.

Domaines: Physique [physics]

Guido Huijsmans, D C van Vugt, S Franssen, S Q Korving, Marina Becoulet. Non-linear MHD Simulations of ELMs in a High Recycling Divertor. 46th European Physical Society Conference on Plasma Physics (EPS 2019), Jul 2019, Milan, Italy. ⟨cea-02555093⟩