Theory of Enhanced Reversed Shear Mode in Tokamaks
نویسندگان
چکیده
It is shown that toroidal magnetic field ripple induced particle flux can drive poloidal E ×B speed to bifurcate over the local maximum of the nonlinear poloidal (or parallel) viscosity. Here, E is the electric field and B is the magnetic field. This mechansim, together with the turbulence suppression due to the radial gradient of the E ×B and diamagnetic angular velocity, is employed to explain enhanced reversed shear mode observed in the core region of tokamaks.
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