Spatiotemporal dynamics and transport reduction in helical magnetic configuration

Rajković, Milan; Watanabe, Tomo-Hiko; Škoric, Miloš
September 2009
Physics of Plasmas;Sep2009, Vol. 16 Issue 9, p092306
Academic Journal
Effects of multihelicity confinement magnetic fields on turbulent transport and zonal flows are investigated by means of spatiotemporal analysis of gyrokinetic Vlasov simulation results for the ion temperature gradient turbulence, where the standard and the inward-shifted configurations of the Large Helical Device are considered. The analysis of simulation results demonstrates that fluctuations of electrostatic potential for zonal flows exhibit spatiotemporal chaos in both configurations. However, the intensity of chaos found is considerably decreased in the inward-shifted configuration consistent with improved confinement. Enhanced zonal flow generation in the inward shifted case is accompanied by transport reduction which may be a direct consequence of chaos suppression.


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