Comparison of a 2D nonlocal transport model to ECRH experiments in LHD

Abstract

A recently developed model of nonlocal transport in two dimensions (2D), the “iterative method” [J. E. Maggs and G. J. Morales, Phys. Rev. E 99, 013307 (2019)], is applied to the published results of ECRH experiments [Takahashi et al. AIP Conf. Proc. 1580, 145 (2014)] performed in the Large Helical Device. It is found from the temperature profiles obtained from the 2D model that the sharply peaked electron temperature profiles observed in such experiments, and previously associated with local transport and “internal transport barriers” or Core Electron-Root Confinement, are also consistent with nonlocal transport. It is shown that the iterative method is suited to handling both scenarios.