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arXiv · 2307.13351

Effect of resonance magnetic perturbation on edge-core turbulence spreading in a tokamak plasma

Guangzhi Ren·Lai Wei·Zheng-Xiong Wang·Jiquan Li
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Abstract

Turbulence spreading from edge to core region with resonance magnetic perturbation (RMP) is investigated using an electromagnetic Landau-fluid model in toroidal geometry. When RMP field with appropriate amplitude are employed in the simulation, long wavelength fluctuations around the resonance surface are excited due to the forced magnetic reconnection. Strong shear flow at the magnetic island separatrix are observed, and break the radial elongated vortex structures of the turbulent fluctuation. The inward flux could be blocked by this shear flow and the saturation level in the core region declines.

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Guangzhi Ren, Lai Wei, Zheng-Xiong Wang, Jiquan Li. 2023-07-25. Effect of resonance magnetic perturbation on edge-core turbulence spreading in a tokamak plasma. https://arxiv.org/abs/2307.13351

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