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Title: Prediction of Alfvén eigenmode energetic particle transport in ITER scenarios with a critical gradient model

Abstract

A reduced 1D, local, critical-gradient model of energetic particle (EP) transport by Alfvén eigenmodes (AEs)—the TGLF-EP+Alpha model—is applied to a much-studied ITER base case and variations with lower plasma current and lower current penetration. The TGLF-EP+Alpha model is a greatly reduced and computationally inexpensive model of EP transport. Such a reduced critical gradient model, while inapplicable to transport driven by strongly nonlinear or non-local abrupt events, is a valuable tool for scoping studies needed in scenario optimization for ITER and beyond. Furthermore, it relies on the assumption of critical-gradient AE transport with the critical EP density gradient determined by linear AE stability calculations in the TGLF gyro-Landau fluid code automated with the parallel-processed TGLF-EP wrapper. EP transport is treated with simultaneous drive of AEs by fusion-born alpha particles and fast ions born from a 1 MeV neutral beam injection (NBI) heating. The effect of simultaneous drive creates about 50% increased particle transport in both EP channels. High magnetic safety factor q and low shear $$\hat{s}$$ are generally destabilizing to AEs, but low shear tends to be more important. A tailored q-profile, steady-staterelevant scenario can reduce AE-induced EP redistribution by better than 25% over the ITER base case despite having half the total current.

Authors:
ORCiD logo [1]; ORCiD logo [2]
  1. Univ. of California, San Diego, CA (United States). Dept. of Physics
  2. General Atomics, San Diego, CA (United States)
Publication Date:
Research Org.:
General Atomics, San Diego, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1597824
Grant/Contract Number:  
[SC0018108; FG02-95ER54309]
Resource Type:
Accepted Manuscript
Journal Name:
Nuclear Fusion
Additional Journal Information:
[ Journal Volume: 60; Journal Issue: 1]; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Alfvén eigenmodes; energetic particles; ITER; transport

Citation Formats

Bass, E. M., and Waltz, R. E. Prediction of Alfvén eigenmode energetic particle transport in ITER scenarios with a critical gradient model. United States: N. p., 2019. Web. doi:10.1088/1741-4326/ab54fb.
Bass, E. M., & Waltz, R. E. Prediction of Alfvén eigenmode energetic particle transport in ITER scenarios with a critical gradient model. United States. doi:10.1088/1741-4326/ab54fb.
Bass, E. M., and Waltz, R. E. Mon . "Prediction of Alfvén eigenmode energetic particle transport in ITER scenarios with a critical gradient model". United States. doi:10.1088/1741-4326/ab54fb.
@article{osti_1597824,
title = {Prediction of Alfvén eigenmode energetic particle transport in ITER scenarios with a critical gradient model},
author = {Bass, E. M. and Waltz, R. E.},
abstractNote = {A reduced 1D, local, critical-gradient model of energetic particle (EP) transport by Alfvén eigenmodes (AEs)—the TGLF-EP+Alpha model—is applied to a much-studied ITER base case and variations with lower plasma current and lower current penetration. The TGLF-EP+Alpha model is a greatly reduced and computationally inexpensive model of EP transport. Such a reduced critical gradient model, while inapplicable to transport driven by strongly nonlinear or non-local abrupt events, is a valuable tool for scoping studies needed in scenario optimization for ITER and beyond. Furthermore, it relies on the assumption of critical-gradient AE transport with the critical EP density gradient determined by linear AE stability calculations in the TGLF gyro-Landau fluid code automated with the parallel-processed TGLF-EP wrapper. EP transport is treated with simultaneous drive of AEs by fusion-born alpha particles and fast ions born from a 1 MeV neutral beam injection (NBI) heating. The effect of simultaneous drive creates about 50% increased particle transport in both EP channels. High magnetic safety factor q and low shear $\hat{s}$ are generally destabilizing to AEs, but low shear tends to be more important. A tailored q-profile, steady-staterelevant scenario can reduce AE-induced EP redistribution by better than 25% over the ITER base case despite having half the total current.},
doi = {10.1088/1741-4326/ab54fb},
journal = {Nuclear Fusion},
number = [1],
volume = [60],
place = {United States},
year = {2019},
month = {12}
}

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Works referenced in this record:

Toroidal gyro‐Landau fluid model turbulence simulations in a nonlinear ballooning mode representation with radial modes
journal, July 1994

  • Waltz, R. E.; Kerbel, G. D.; Milovich, J.
  • Physics of Plasmas, Vol. 1, Issue 7
  • DOI: 10.1063/1.870934

1.5D quasilinear model and its application on beams interacting with Alfvén eigenmodes in DIII-D
journal, September 2012

  • Ghantous, K.; Gorelenkov, N. N.; Berk, H. L.
  • Physics of Plasmas, Vol. 19, Issue 9
  • DOI: 10.1063/1.4752011

Energetic ion distribution resulting from neutral beam injection in tokamaks
journal, October 1976


Kinetic transport simulation of energetic particles
journal, April 2016


Simulations tackle abrupt massive migrations of energetic beam ions in a tokamak plasma
journal, August 2018


ITER predictions using the GYRO verified and experimentally validated trapped gyro-Landau fluid transport model
journal, June 2011


Gyrokinetic simulations of impurity, He ash and α particle transport and consequences on ITER transport modelling
journal, April 2009


Anomalous Transport Scaling in the DIII-D Tokamak Matched by Supercomputer Simulation
journal, July 2003


Nonlinear Dynamics of a Driven Mode near Marginal Stability
journal, February 1996


Density limits in toroidal plasmas
journal, July 2002


Observation of Critical-Gradient Behavior in Alfvén-Eigenmode-Induced Fast-Ion Transport
journal, February 2016


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

Prediction of the fusion alpha density profile in ITER from local marginal stability to Alfvén eigenmodes
journal, October 2014


Gyrokinetic simulations of mesoscale energetic particle-driven Alfvénic turbulent transport embedded in microturbulence
journal, November 2010

  • Bass, E. M.; Waltz, R. E.
  • Physics of Plasmas, Vol. 17, Issue 11
  • DOI: 10.1063/1.3509106

Development and validation of a predictive model for the pedestal height
journal, May 2009

  • Snyder, P. B.; Groebner, R. J.; Leonard, A. W.
  • Physics of Plasmas, Vol. 16, Issue 5
  • DOI: 10.1063/1.3122146

Enhanced Localized Energetic-Ion Losses Resulting from Single-Pass Interactions with Alfvén Eigenmodes
journal, February 2013


A theory-based transport model with comprehensive physics
journal, May 2007

  • Staebler, G. M.; Kinsey, J. E.; Waltz, R. E.
  • Physics of Plasmas, Vol. 14, Issue 5
  • DOI: 10.1063/1.2436852

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

Turbulent transport of alpha particles in reactor plasmas
journal, November 2006

  • Estrada-Mila, C.; Candy, J.; Waltz, R. E.
  • Physics of Plasmas, Vol. 13, Issue 11
  • DOI: 10.1063/1.2364149

Test-electron analysis of the magnetic reconnection topology
journal, December 2017

  • Borgogno, D.; Perona, A.; Grasso, D.
  • Physics of Plasmas, Vol. 24, Issue 12
  • DOI: 10.1063/1.5004613

The effect of the fast-ion profile on Alfvén eigenmode stability
journal, August 2013


Energetic particle physics in fusion research in preparation for burning plasma experiments
journal, November 2014