Effect of resonant magnetic perturbation on edge–core turbulence spreading in a tokamak plasma

Abstract

Turbulence spreading from edge to core region of tokamak with a resonant magnetic perturbation (RMP) is investigated using an electromagnetic Landau-fluid model in a toroidal geometry. As RMP field with an appropriate amplitude is applied, long wavelength fluctuations around the resonance surface can be excited due to the forced magnetic reconnection. Strong shear flow at the magnetic island separatrix is observed, which can break the radially elongated vortex structures of the turbulent fluctuation. The inward turbulence spreading can be blocked by this shear flow, and the saturation level of turbulence intensity in the core region declines.