Bremen 2017 – wissenschaftliches Programm
P 11.6: Vortrag
Dienstag, 14. März 2017, 16:05–16:30, HS 1010
Theory-based modeling of L-mode plasma intrinsic rotation in ASDEX Upgrade — •Ivan Erofeev, Emiliano Fable, Clemente Angioni, William Hornsby, Rachael McDermott, and the ASDEX Upgrade Team — Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching, Germany
Many tokamak plasmas have been found to develop finite toroidal rotation velocity from rest without external sources of torque, and L-mode plasmas tend to flip the rotation direction in the core twice - from co- to counter-current and back again - as the density grows. This phenomenon is known as intrinsic rotation and is believed to be caused by a component of the stress tensor not related to either viscosity or pinch. This residual stress appears as a consequence of the poloidal symmetry violation.
In this work we investigate the effect of non-zero, poloidally averaged, parallel wavenumbers of plasma microinstabilities like TEM and ITG modes, which arise from finite tilting angles of the turbulent structures. We perform simulations of L-mode plasma experiments in ASDEX Upgrade with the ASTRA code, coupled to the TGLF transport model, and the drift-kinetic solver NEO. We estimate the values of the tilting angles and the average parallel wavenumbers from TGLF linear turbulent spectra, which are necessary to match the experimental toroidal velocity profiles. We then compare the results to global gyrokinetic simulations with the GKW code.