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Title: DIII-D shaping demonstrates correlation of intrinsic momentum with energy

Journal Article · · Nuclear Fusion

Scaling of intrinsic rotation in DIII-D H-mode plasmas demonstrates a strong correlation with the ion temperature (T i) and stored plasma thermal energy, indicating a coupling between the turbulent intrinsic momentum flux and the turbulent energy flux. We consider intrinsic rotation to be the toroidal rotation in axisymmetric conditions with no external momentum injection. The DIII-D dimensionless empirical scaling of intrinsic rotation with plasma stored energy has been recently tested by novel experiments on DIII-D that utilize relatively small variations in the plasma shape, namely the triangularity, to modify the intrinsic rotation. Shape variation affects the intrinsic rotation by modifying the turbulent transport, rather than via changes in the auxiliary heating power, or applied torque. These H-modes are heated by ECH with no external torque input. Balanced torque blips from neutral beams measure the ion flow velocity and T i. Higher thermal energy and intrinsic angular momentum are correlated with higher triangularity. Turbulent density fluctuations in the pedestal region show a significantly higher level at lower triangularity, with lower energy confinement, possibly the source of greater transport. In DIII-D, the E x B shear, which is mainly driven by the edge pressure gradient term in intrinsic rotation conditions, could provide the dominant symmetry breaking necessary for generating a net turbulent momentum stress and qualitatively agree with the scaling.

Research Organization:
General Atomics, San Diego, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
Grant/Contract Number:
FC02-04ER54698
OSTI ID:
1568807
Journal Information:
Nuclear Fusion, Vol. 59, Issue 9; ISSN 0029-5515
Publisher:
IOP ScienceCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

References (27)

Intrinsic torque reversals induced by magnetic shear effects on the turbulence spectrum in tokamak plasmasa) journal May 2015
An overview of charge-exchange spectroscopy as a plasma diagnostic journal February 1994
Momentum and thermal transport in neutral-beam-heated tokamaks journal January 1988
Toroidal rotation in neutral beam heated discharges in DIII-D journal January 2003
Observations of impurity toroidal rotation suppression with ITB formation in ICRF and ohmic H mode Alcator C-Mod plasmas journal March 2001
Intrinsic rotation in DIII-D journal May 2007
Gyrokinetic simulation of momentum transport with residual stress from diamagnetic level velocity shears journal April 2011
Intrinsic rotation driven by the electrostatic turbulence in up-down asymmetric toroidal plasmas journal June 2009
Parasitic momentum flux in the tokamak core journal March 2017
Characterization of intrinsic rotation drive on DIII-D journal May 2011
Measurements of the deuterium ion toroidal rotation in the DIII-D tokamak and comparison to neoclassical theory journal May 2012
Validation of the kinetic-turbulent-neoclassical theory for edge intrinsic rotation in DIII-D journal May 2018
Neoclassical ion transport in rotating axisymmetric plasmas journal January 1985
Mechanisms for generating toroidal rotation in tokamaks without external momentum input journal May 2010
Toroidal rotation in ICRF-heated H-modes on JET journal January 1997
Main ion and impurity edge profile evolution across the L- to H-mode transition on DIII-D journal August 2018
ITER predictions using the GYRO verified and experimentally validated trapped gyro-Landau fluid transport model journal June 2011
Intrinsic toroidal velocity near the edge of DIII-D H-mode plasmas journal July 2009
A novel, multichannel, comb-frequency Doppler backscatter system journal October 2010
On the efficiency of intrinsic rotation generation in tokamaks journal October 2010
Inter-machine comparison of intrinsic toroidal rotation in tokamaks journal October 2007
The effect of plasma shape on H-mode pedestal characteristics on DIII-D journal May 2000
Core barrier formation near integer q surfaces in DIII-D journal August 2006
Effect of resonant and non-resonant magnetic braking on error field tolerance in high beta plasmas journal September 2009
Dimensionless size scaling of intrinsic rotation in DIII-D journal August 2016
Predicting rotation for ITER via studies of intrinsic torque and momentum transport in DIII-D journal May 2017
Parasitic Momentum Flux in the Tokamak Core text January 2016

Figures / Tables (6)