Transport events and E x B staircase in flux-driven gyrokinetic simulation of ion temperature gradient turbulence

Abstract

Nonlocal bursty heat transport can be pervasive in fusion plasmas, often leading to deviation from the gyro-Bohm scaling. Recently, radially quasi-periodic structures of E x B shear layers called the E x B staircase have been identified in fluxdriven gyrokinetic simulations, and their basic properties have been recognized. In this study, we investigate heat transport events and the E x B staircase from the GyroKinetic-based Numerical Experiment of Tokamak (GKNET) [Imadera et al., IAEA-FEC, TH/P5-8 (2014)] flux-driven gyrokinetic simulation of ion temperature gradient (ITG) turbulence. We classify the nonlocal heat transport events according to characteristics of their interaction with the E x B staircase models are elucidated.