Energetic ion transport by microturbulence is insignificant in tokamaks

201337 citationsJournal Articlebronze Open Access

Authors

D. C. Pace · General Atomics (United States)

M. E. Austin · The University of Texas at Austin

E.M. Bass · University of California, San Diego

R. Budny · Princeton Plasma Physics Laboratory

W. W. Heidbrink · University of California, Irvine

J. C. Hillesheim · University of California, Los Angeles

C. T. Holcomb

Abstract

Energetic ion transport due to microturbulence is investigated in magnetohydrodynamic-quiescent plasmas by way of neutral beam injection in the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)]. A range of on-axis and off-axis beam injection scenarios are employed to vary relevant parameters such as the character of the background microturbulence and the value of Eb/Te, where Eb is the energetic ion energy and Te the electron temperature. In all cases, it is found that any transport enhancement due to microturbulence is too small to observe experimentally. These transport effects are modeled using numerical and analytic expectations that calculate the energetic ion diffusivity due to microturbulence. It is determined that energetic ion transport due to coherent fluctuations (e.g., Alfvén eigenmodes) is a considerably larger effect and should therefore be considered more important for ITER.

Topics & Keywords

Magnetic confinement fusion research Fusion materials and technologies Ionosphere and magnetosphere dynamics

UN Sustainable Development Goals

Affordable and clean energy

Publication Details

Published in: Physics of Plasmas

Volume 20, Issue 5

DOI: 10.1063/1.4803930

Field-Weighted Citation Impact: 8.83