Parts | Days | Selection | Search | Updates | Downloads | Help
P: Fachverband Plasmaphysik
P 17: Poster II
P 17.37: Poster
Friday, September 3, 2021, 14:00–16:00, P
Simulations of massive Deuterium injection into an MHD active ASDEX Upgrade plasma — •Fabian Wieschollek1, Matthias Hoelzl1, Eric Nardon2, the JOREK Team3, and the ASDEX Upgrade Team4 — 1Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching b. M., Germany — 2CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France — 3See the author list of M. Hoelzl et al 2021 NF 61, 065001 — 4See the author list of H. Meyer et al 2019, NF 59, 112014
The foreseen disruption mitigation strategy for ITER is shattered pellet injection (SPI). In a realistic disruption scenario, the SPI is being triggered, when the plasma has already become MHD active; in particular 2/1 neoclassical tearing modes (NTM) are often present.
In this work, we investigate the interaction of Deuterium SPI and a pre-existing 2/1 NTM in ASDEX Upgrade to assess its potential impact onto the mitigation strategy by means of the non-linear MHD code JOREK. Scans are performed of the initial island width, the number of atoms injected, and the relative injection phase with respect to the island O-point. Results indicate that preexisting islands do not render the mitigation ineffective. In case of small initial island sizes, no significant influence onto thermal quench (TQ) timing is observed independently of the injection phase. In case of larger islands, a delayed island growth and TQ onset is observed. This observation only changes when the injection is located to the direct vicinity of the X-point.
The studies are currently extended to take background impurities and multiple injection points into account.