Ion temperature gradient driven turbulence in the weak density gradient limit

Abstract

The anomalous heat transport arising from the ion temperature gradient driven mode or ηi-mode turbulence is extended to the range of the weak density gradient limit (ηi=Ln/LT→∞), which is appropriate for H-mode dishcarges. It is shown that the anomalous ion heat conductivity χi with Ln→∞ scales as χi=g(ρs/LT) (cTi/eB) exp(−βσ) with σ=(Te/Ti) (LT/Ls), β≂4, and g≂1. This χi scaling is the natural extension for high ηi of the scaling of χi for K=(Ti/Te) (1+ηi)≲4 obtained [Phys. Fluids B 2, 1833 (1990)] from analytical and numerical studies.