Plasma size and power scaling of ion temperature gradient driven turbulence

Idomura, Yasuhiro   ; Nakata, Motoki

The transport scaling with respect to plasma size and heating power is studied for ion temperature gradient driven turbulence using a fixed-flux full- gyrokinetic Eulerian code. It is found that when heating power is scaled with plasma size, the ion heat diffusivity increases with plasma size in a local limit regime, where simulations predict a gyro-Bohm scaling. In the local limit regime, the transport scaling is strongly affected by the stiffness of ion temperature profiles, which is related to the power degradation of confinement.