Bochum 2015 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

P: Fachverband Plasmaphysik

P 22: Helmholtz Graduate School for Plasma Physics II

P 22.1: Fachvortrag

Wednesday, March 4, 2015, 16:30–16:55, HZO 50

Confinement and stability of plasmas with externally driven steady-state elevated q-profiles — •Alexander Bock, Jörg Stober, Rainer Fischer, Emiliano Fable, Matthias Reich, and ASDEX Upgrade Team — Max-Planck-Institut für Plasmaphysik, Garching bei München, Deutschland

The helicity profile of the magnetic field lines is an important quantity for the operation of Tokamak fusion devices and can be expressed as the so-called safety factor q. It has profound influence on both the stability of the fusion plasma, as well as its confinement properties.

Operation scenarios with centrally elevated and flat, or even reversed q-profiles promise fewer central instabilities and better core confinement and are thus considered potentially attractive for future fusion power plants. To verify these predictions, centrally elevated q-profiles are created using external counter current drive, with additional heating power added afterwards to explore the stability limits and transport properties of the resulting plasmas. The tailored q-profiles are calculated using magnetic equilibrium reconstruction constrained by internal motional Stark effect data to confirm to the presence of the desired helicities. They are then used as a basis for simulations of the transport properties with the gyro-Landau-fluid code TGLF. The simulation results are then compared to the experimentally measured kinetic profiles.