Understanding LOC/SOC Phenomenology in Tokamaks
Name
20ja006_full.pdf
Size
2.14 MB
Format
Adobe PDF
Checksum (MD5)
aca53bd1edd0a12b5cd1f4651d64c491
Author(s)
Rice, John E.
Citrin, J.
Cao, N.M.
Diamond, P.H.
Fable, E.
Greenwald, M.
Grierson, B.A.
Date Issued
February 2020
Journal
Nuclear Fusion
Publisher
IOP
Abstract
Phenomenology of Ohmic energy confinement saturation in tokamaks is reviewed. Characteristics of the linear Ohmic confinement (LOC) and saturated Ohmic confinement (SOC) regimes are documented and transformations in all transport channels across the LOC/SOC transition are described, including rotation reversals, ``non-local'' cut-off and density peaking, in addition to dramatic changes in fluctuation intensity. Unification of results from nearly 20 devices indicates that the LOC/SOC transition occurs at a critical value of the product of the density, edge safety factor and device major radius, and that this product increases with toroidal magnetic field. Comparison with gyro-kinetic simulations suggests that the effects of sub-dominant TEMs are important in the LOC regime while ITG mode turbulence dominates with SOC.
Description
Submitted for publication in Nuclear Fusion
MIT Department
Massachusetts Institute of Technology. Plasma Science and Fusion Center
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1088/1741-4326/abac4b
