skip to main content

DOE PAGESDOE PAGES

Title: A model of the saturation of coupled electron and ion scale gyrokinetic turbulence

A new paradigm of zonal flow mixing as the mechanism by which zonal E × B fluctuations impact the saturation of gyrokinetic turbulence has recently been deduced from the nonlinear 2D spectrum of electric potential fluctuations in gyrokinetic simulations. These state of the art simulations span the physical scales of both ion and electron turbulence. It was found that the zonal flow mixing rate, rather than zonal flow shearing rate, competes with linear growth at both electron and ion scales. A model for saturation of the turbulence by the zonal flow mixing was developed and applied to the quasilinear trapped gyro-Landau fluid transport model (TGLF). The first validation tests of the new saturation model are reported in this paper with data from L-mode and high-β p regime discharges from the DIII-D tokamak. Lastly, the shortfall in the predicted L-mode edge electron energy transport is improved with the new saturation model for these discharges but additional multiscale simulations are required in order to verify the safety factor and collisionality dependencies found in the modeling.
Authors:
 [1] ;  [2] ;  [1] ;  [3]
  1. General Atomics, San Diego, CA (United States)
  2. Oak Ridge Institute for Science Education (ORISE), Oak Ridge, TN (United States)
  3. Univ. of California San Diego (UCSD), La Jolla, CA (United States)
Publication Date:
Grant/Contract Number:
FC02-04ER54698
Type:
Accepted Manuscript
Journal Name:
Nuclear Fusion
Additional Journal Information:
Journal Volume: 57; Journal Issue: 6; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Research Org:
General Atomics, San Diego, CA (United States)
Sponsoring Org:
USDOE Office of Nuclear Energy (NE)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; gyrokinetic turbulence; zonal flows; multi-scale transport; L-mode transport shortfall; tokamak transport
OSTI Identifier:
1374837

Staebler, Gary M., Howard, Nathan T., Candy, Jeffrey M., and Holland, Christopher G.. A model of the saturation of coupled electron and ion scale gyrokinetic turbulence. United States: N. p., Web. doi:10.1088/1741-4326/aa6bee.
Staebler, Gary M., Howard, Nathan T., Candy, Jeffrey M., & Holland, Christopher G.. A model of the saturation of coupled electron and ion scale gyrokinetic turbulence. United States. doi:10.1088/1741-4326/aa6bee.
Staebler, Gary M., Howard, Nathan T., Candy, Jeffrey M., and Holland, Christopher G.. 2017. "A model of the saturation of coupled electron and ion scale gyrokinetic turbulence". United States. doi:10.1088/1741-4326/aa6bee. https://www.osti.gov/servlets/purl/1374837.
@article{osti_1374837,
title = {A model of the saturation of coupled electron and ion scale gyrokinetic turbulence},
author = {Staebler, Gary M. and Howard, Nathan T. and Candy, Jeffrey M. and Holland, Christopher G.},
abstractNote = {A new paradigm of zonal flow mixing as the mechanism by which zonal E × B fluctuations impact the saturation of gyrokinetic turbulence has recently been deduced from the nonlinear 2D spectrum of electric potential fluctuations in gyrokinetic simulations. These state of the art simulations span the physical scales of both ion and electron turbulence. It was found that the zonal flow mixing rate, rather than zonal flow shearing rate, competes with linear growth at both electron and ion scales. A model for saturation of the turbulence by the zonal flow mixing was developed and applied to the quasilinear trapped gyro-Landau fluid transport model (TGLF). The first validation tests of the new saturation model are reported in this paper with data from L-mode and high-βp regime discharges from the DIII-D tokamak. Lastly, the shortfall in the predicted L-mode edge electron energy transport is improved with the new saturation model for these discharges but additional multiscale simulations are required in order to verify the safety factor and collisionality dependencies found in the modeling.},
doi = {10.1088/1741-4326/aa6bee},
journal = {Nuclear Fusion},
number = 6,
volume = 57,
place = {United States},
year = {2017},
month = {5}
}