Reduction of Turbulent Transport with Zonal Flows Enhanced in Helical Systems
- Resource Type
- Authors
- Hideo Sugama; S. Ferrando-Margalet; Tomo-Hiko Watanabe
- Source
- Physical Review Letters. 100:195002
- Subject
- Physics
Fusion
Turbulence
Ripple
General Physics and Astronomy
Ion temperature
Plasma
Mechanics
Zonal flow (plasma)
Physics::Fluid Dynamics
Large Helical Device
Physics::Plasma Physics
Physics::Space Physics
Atomic physics
Reduction (mathematics)
- Language
- English
Gyrokinetic Vlasov simulations of the ion temperature gradient turbulence are performed in order to investigate effects of helical magnetic configurations on turbulent transport and zonal flows. The obtained results confirm the theoretical prediction that helical configurations optimized for reducing neoclassical ripple transport can simultaneously reduce the turbulent transport with enhancing zonal-flow generation. Stationary zonal-flow structures accompanied with transport reduction are clearly identified by the simulation for the neoclassically optimized helical geometry. The generation of the stationary zonal flow explains a physical mechanism for causing the confinement improvement observed in the inward-shifted plasma in the Large Helical Device [O. Motojima et al., Nucl. Fusion 43, 1674 (2003)].