DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Theory of transport in high bootstrap fraction H-modes with internal transport barriers

Abstract

A review of the recent progress in understanding the transport in fully non-inductive, high bootstrap fraction H-mode discharges, developed on the DIII-D tokamak, is given in this paper. Experiments have demonstrated improved energy confinement due to the formation of an internal transport barrier in high bootstrap fraction H-mode discharges. Gyrokinetic analysis, and quasi-linear predictive modeling, demonstrates that the observed transport barrier is due to the suppression of turbulence, primarily due to the large Shafranov shift. ExB velocity shear does not play a significant role in the transport barrier due to the high safety factor. The ion energy transport is reduced to neoclassical for DIII-D discharges and electron energy and particle transport is reduced, but still turbulent, within the barrier. Deeper into the plasma, high levels of electron transport are observed. The electron energy transport in DIII-D is found to be due to electromagnetically enhanced electron scale modes. A contribution from fast ion driven instabilities is also possible. The kinetic ballooning mode plays a strong role in the region between the internal and H-mode edge transport barriers with two types of self-organized pedestal states observed.

Authors:
 [1]
  1. General Atomics, San Diego, CA (United States)
Publication Date:
Research Org.:
General Atomics, San Diego, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1567843
Grant/Contract Number:  
FC02-04ER54698
Resource Type:
Accepted Manuscript
Journal Name:
Nuclear Fusion
Additional Journal Information:
Journal Volume: 58; Journal Issue: 11; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Staebler, Gary M. Theory of transport in high bootstrap fraction H-modes with internal transport barriers. United States: N. p., 2018. Web. doi:10.1088/1741-4326/aac4b7.
Staebler, Gary M. Theory of transport in high bootstrap fraction H-modes with internal transport barriers. United States. https://doi.org/10.1088/1741-4326/aac4b7
Staebler, Gary M. Thu . "Theory of transport in high bootstrap fraction H-modes with internal transport barriers". United States. https://doi.org/10.1088/1741-4326/aac4b7. https://www.osti.gov/servlets/purl/1567843.
@article{osti_1567843,
title = {Theory of transport in high bootstrap fraction H-modes with internal transport barriers},
author = {Staebler, Gary M.},
abstractNote = {A review of the recent progress in understanding the transport in fully non-inductive, high bootstrap fraction H-mode discharges, developed on the DIII-D tokamak, is given in this paper. Experiments have demonstrated improved energy confinement due to the formation of an internal transport barrier in high bootstrap fraction H-mode discharges. Gyrokinetic analysis, and quasi-linear predictive modeling, demonstrates that the observed transport barrier is due to the suppression of turbulence, primarily due to the large Shafranov shift. ExB velocity shear does not play a significant role in the transport barrier due to the high safety factor. The ion energy transport is reduced to neoclassical for DIII-D discharges and electron energy and particle transport is reduced, but still turbulent, within the barrier. Deeper into the plasma, high levels of electron transport are observed. The electron energy transport in DIII-D is found to be due to electromagnetically enhanced electron scale modes. A contribution from fast ion driven instabilities is also possible. The kinetic ballooning mode plays a strong role in the region between the internal and H-mode edge transport barriers with two types of self-organized pedestal states observed.},
doi = {10.1088/1741-4326/aac4b7},
journal = {Nuclear Fusion},
number = 11,
volume = 58,
place = {United States},
year = {Thu Sep 27 00:00:00 EDT 2018},
month = {Thu Sep 27 00:00:00 EDT 2018}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 15 works
Citation information provided by
Web of Science

Figures / Tables:

Fig. 1 Fig. 1: (Fig. 1 of [1]) Time traces for selected plasma parameters for DⅢ-D discharge 154406.

Save / Share:

Works referenced in this record:

Synergism between cross-section and profile shaping in beta optimization of tokamak equilibria with negative central shear
journal, October 1998


Trapped gyro-Landau-fluid transport modeling of DIII-D hybrid discharges
journal, December 2010

  • Kinsey, J. E.; Staebler, G. M.; Petty, C. C.
  • Physics of Plasmas, Vol. 17, Issue 12
  • DOI: 10.1063/1.3523058

An Eulerian gyrokinetic-Maxwell solver
journal, April 2003


Stabilizing impact of high gradient of β on microturbulence
journal, July 2003

  • Bourdelle, C.; Dorland, W.; Garbet, X.
  • Physics of Plasmas, Vol. 10, Issue 7
  • DOI: 10.1063/1.1585032

Alfvén eigenmode stability and critical gradient energetic particle transport using the Trapped-Gyro-Landau-Fluid model
journal, July 2017

  • Sheng, He; Waltz, R. E.; Staebler, G. M.
  • Physics of Plasmas, Vol. 24, Issue 7
  • DOI: 10.1063/1.4989716

The first transport code simulations using the trapped gyro-Landau-fluid model
journal, May 2008

  • Kinsey, J. E.; Staebler, G. M.; Waltz, R. E.
  • Physics of Plasmas, Vol. 15, Issue 5
  • DOI: 10.1063/1.2889008

A high-accuracy Eulerian gyrokinetic solver for collisional plasmas
journal, November 2016


Gyrokinetic simulation of global and local Alfvén eigenmodes driven by energetic particles in a DIII-D discharge
journal, January 2013

  • Bass, E. M.; Waltz, R. E.
  • Physics of Plasmas, Vol. 20, Issue 1
  • DOI: 10.1063/1.4773177

Development of high poloidal beta, steady-state scenario with ITER-like tungsten divertor on EAST
journal, June 2017


Progress toward steady-state tokamak operation exploiting the high bootstrap current fraction regime
journal, June 2016

  • Ren, Q. L.; Garofalo, A. M.; Gong, X. Z.
  • Physics of Plasmas, Vol. 23, Issue 6
  • DOI: 10.1063/1.4948724

Shear, Periodicity, and Plasma Ballooning Modes
journal, February 1978


Gyro-Landau fluid equations for trapped and passing particles
journal, October 2005

  • Staebler, G. M.; Kinsey, J. E.; Waltz, R. E.
  • Physics of Plasmas, Vol. 12, Issue 10
  • DOI: 10.1063/1.2044587

Transport modeling of the DIII-D high ${{\beta}_{p}}$ scenario and extrapolations to ITER steady-state operation
journal, August 2017


Chapter 2: Plasma confinement and transport
journal, December 1999

  • Transport, ITER Physics Expert Group on Confin; Database, ITER Physics Expert Group on Confin; Editors, ITER Physics Basis
  • Nuclear Fusion, Vol. 39, Issue 12
  • DOI: 10.1088/0029-5515/39/12/302

The role of zonal flows in the saturation of multi-scale gyrokinetic turbulence
journal, June 2016

  • Staebler, G. M.; Candy, J.; Howard, N. T.
  • Physics of Plasmas, Vol. 23, Issue 6
  • DOI: 10.1063/1.4954905

Bootstrap current in a tokamak
journal, September 1994


Kinetic calculation of neoclassical transport including self-consistent electron and impurity dynamics
journal, July 2008


Confinement improvement in the high poloidal beta regime on DIII-D and application to steady-state H-mode on EAST
journal, May 2017

  • Ding, S.; Garofalo, A. M.; Qian, J.
  • Physics of Plasmas, Vol. 24, Issue 5
  • DOI: 10.1063/1.4982058

Compatibility of internal transport barrier with steady-state operation in the high bootstrap fraction regime on DIII-D
journal, November 2015


Transport barriers in bootstrap-driven tokamaks
journal, May 2018

  • Staebler, G. M.; Garofalo, A. M.; Pan, C.
  • Physics of Plasmas, Vol. 25, Issue 5
  • DOI: 10.1063/1.5019282

Works referencing / citing this record:

The dominant micro-turbulence instabilities in the lower q 95 high β p plasmas on DIII-D and predict-first extrapolation
journal, November 2019


Persistence of Ion Temperature Gradient Turbulent Transport at Finite Normalized Pressure
journal, July 2019


Key effects on the confinement improvement of the ASDEX Upgrade hybrid scenario
journal, September 2019


Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.