(TH/P8-16) Transport due to Electromagnetic Turbulence in Externally Heated Plasma

A. Ishizawa1), N. Nakajima1)
1) National Institute for Fusion Science, Toki, Japan

Abstract.  Turbulent transport caused by multi-scale interactions among electromagnetic micro-turbulence, tearing mode, and zonal flow is investigated by numerically solving a reduced set of two-fluid equations. A new three-dimensional numerical simulation of transport phenomena in an open system controlled by external heat source and sink is proposed by virtue of self-consistent calculation of the multi-scale interactions. When tearing mode appears in a quasi-equilibrium including micro-turbulence and zonal flow, the energy spectrum of micro-turbulence is changed so that the energy of the dominant toroidal mode representing micro-turbulence is reduced and the energy of small toroidal mode including tearing mode increases. At the same time the ion temperature profile is flattened and thermal diffusion coefficient increases around the magnetic islands due to tearing mode. The zonal flow shear becomes strong around the magnetic island.

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