Spatiotemporal Chaos, Stochasticity and Transport in Toroidal magnetic Configurations
نویسنده
چکیده
In order to get a more complete insight into the transport processes, zonal flow dynamics and the nature of stochasticity in toroidal systems (helical and tokamak) we analyze nonlinear gyrokinetic Vlasov simulation (GKV) results for the tokamak and the standard and the inward shifted helical configurations from the aspect of nonlinear dynamic systems theory. In both the tokamak and the helical case we show how stochasticity arises from spatiotemporal chaos (STC) . Reduction of transport in the inward shifted configuration with respect to the standard one is interpreted as a consequence of STC suppression while analogous phenomenon is noticed in the purely temporal behavior of plasma dynamics. Hence, in the helical configuration the inward shifted helical configuration represents means for control of spatiotemporal chaos. Layapunov exponents, evaluated with respect to the complete spatiotemporal dynamics , are shown to be directly related to transport properties.
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