Speaker
Vladimir Pastukhov
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P5.1085.pdf
Toroidal momentum maintenance and transport in simulations of
nonlinear turbulent convection in tokamak core plasmas
V.P. Pastukhov, D.V. Smirnov
NRC "Kurchatov Institute", Moscow, Russian Federation
The paper continues our previous theoretical study and simulations of low-frequency
turbulence and the associated cross-field anomalous transport processes in tokamak core
plasmas [1-3]. The main goal of the paper is simulation of toroidal momentum transport in
the presence of self-consistent nonlinear turbulent plasma convection. Contrary to many
other studies our simulations are based on adiabatically-reduced MHD-like plasma dynamic
model in which the toroidal plasma flows are the natural parts of the nonlinear turbulent
plasma convection [1, 2]. We assume that magnetic field in tokamaks is axi-symmetric with
nested magnetic flux surfaces. As a result, there are inherent conservation laws for the
toroidal momentum and the dynamic vorticity in this model. Code CONTRA-C developed
in a frame of simplified cylindrical model for tokamaks was used for this series of
simulations. Temporal evolution and radial profiles of plasma potential, toroidal
momentum density, and dynamic vorticity in presence of different torque sources are
simulated and analyzed. We consider torque sources those correspond to neutral beam
injection, various symmetry breaking mechanisms, as well as to momentum and vorticity
exchange between plasma core and SOL region at the external boundary of simulation
domain. Special attention is paid to regimes in which conditions for ITB formation near the
major rational surfaces could be satisfied [3].
References
[1] V.P. Pastukhov, N.V. Chudin and D.V. Smirnov, Plasma Phys. and Controlled Fusion 53, 054015
(2011)
[2] V.P. Pastukhov and D.V. Smirnov, Plasma Phys. Reports 42, 307 (2016)
[3] V.P. Pastukhov and D.V. Smirnov, Proceedings of 44th EPS Conference on Plasma Physics, report
P2.173 (http://ocs.ciemat.es/EPS2017PAP/pdf/P2.173.pdf)
