München 2019 – wissenschaftliches Programm
P 18.87: Poster
Donnerstag, 21. März 2019, 16:30–18:30, Foyer Audimax
Towards nonlinear MHD simulations of quasi-axisymmetric stellarators — •Nikita Nikulsin and Matthias Hoelzl — Max Planck Institute for Plasma Physics, Garching, Germany
Quasi-axisymmetric (QA) stellarators present a major improvement in neoclassical confinement over unoptimized stellarators. By imposing the constraint that the magnetic field strength does not depend on the Boozer toroidal angle, particle orbits can be made tokamak-like, significantly improving confinement. In addition to particle orbits, QA stellarators share many other similarities with tokamaks. In particular, the bootstrap current contributes significantly to the rotational transform in a QA device. This raises the question of whether QA stellarators will be prone to disruptions like tokamaks, how these disruptions would compare to tokamak disruptions and whether they can be avoided more easily than in a tokamak. In order to investigate this, nonlinear MHD simulations of QA stellarators will be conducted. Currently, work is underway to derive reduced MHD equations suitable for a QA stellarator and implement them in the JOREK code, which will then be used to simulate various QA configurations.