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Title: Interpretive MHD modeling of dispersive shell pellet injection for rapid shutdown in tokamaks

Abstract

Dispersive shell pellet (DSP) injection is modeled with the extended-MHD code NIMROD for interpretive insight into the results of recent DIII-D DSP experiments and to explore the dynamics of an inside-out thermal quench for disruption mitigation in tokamaks. Simulations of the pre-thermal quench (TQ) phase indicate that the upper bound for the quantity of ablated carbon shell material that will not perturb the flux surfaces is in the ballpark of, but somewhat below the experimental quantity. Even below this quantity, sufficient electrons are added to the plasma by the shell material to produce significant dilution cooling before the TQ is triggered. Simulations carried through the end of the TQ have very large amplitude MHD fluctuations (δB/B>10-2) at the time of the plasma current spike associated with current profile redistribution. Finally, after the plasma current spike, which is of comparable amplitude to that measured in DIII-D experiments, none of the runaway electron test-particles whose orbits are tracked throughout the simulation remain confined.

Authors:
ORCiD logo [1]
  1. Fiat Lux, 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)
OSTI Identifier:
1607855
Alternate Identifier(s):
OSTI ID: 1618152
Report Number(s):
DOE-GA-54309
Journal ID: ISSN 0029-5515; DE-FC02-04ER54698
Grant/Contract Number:  
FG02-95ER54309; FC02-04ER54698; AC02-05CH11231
Resource Type:
Accepted Manuscript
Journal Name:
Nuclear Fusion
Additional Journal Information:
Journal Volume: 60; Journal Issue: 6; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; tokamak; disruption; MHD; mitigation

Citation Formats

Izzo, Valerie A. Interpretive MHD modeling of dispersive shell pellet injection for rapid shutdown in tokamaks. United States: N. p., 2020. Web. doi:10.1088/1741-4326/ab8544.
Izzo, Valerie A. Interpretive MHD modeling of dispersive shell pellet injection for rapid shutdown in tokamaks. United States. doi:https://doi.org/10.1088/1741-4326/ab8544
Izzo, Valerie A. Wed . "Interpretive MHD modeling of dispersive shell pellet injection for rapid shutdown in tokamaks". United States. doi:https://doi.org/10.1088/1741-4326/ab8544. https://www.osti.gov/servlets/purl/1607855.
@article{osti_1607855,
title = {Interpretive MHD modeling of dispersive shell pellet injection for rapid shutdown in tokamaks},
author = {Izzo, Valerie A.},
abstractNote = {Dispersive shell pellet (DSP) injection is modeled with the extended-MHD code NIMROD for interpretive insight into the results of recent DIII-D DSP experiments and to explore the dynamics of an inside-out thermal quench for disruption mitigation in tokamaks. Simulations of the pre-thermal quench (TQ) phase indicate that the upper bound for the quantity of ablated carbon shell material that will not perturb the flux surfaces is in the ballpark of, but somewhat below the experimental quantity. Even below this quantity, sufficient electrons are added to the plasma by the shell material to produce significant dilution cooling before the TQ is triggered. Simulations carried through the end of the TQ have very large amplitude MHD fluctuations (δB/B>10-2) at the time of the plasma current spike associated with current profile redistribution. Finally, after the plasma current spike, which is of comparable amplitude to that measured in DIII-D experiments, none of the runaway electron test-particles whose orbits are tracked throughout the simulation remain confined.},
doi = {10.1088/1741-4326/ab8544},
journal = {Nuclear Fusion},
number = 6,
volume = 60,
place = {United States},
year = {2020},
month = {4}
}

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Works referenced in this record:

First demonstration of rapid shutdown using neon shattered pellet injection for thermal quench mitigation on DIII-D
journal, March 2016


Thermal quench mitigation and current quench control by injection of mixed species shattered pellets in DIII-D
journal, June 2016

  • Shiraki, D.; Commaux, N.; Baylor, L. R.
  • Physics of Plasmas, Vol. 23, Issue 6
  • DOI: 10.1063/1.4954389

Experiments in DIII-D toward achieving rapid shutdown with runaway electron suppression
journal, May 2010

  • Hollmann, E. M.; Commaux, N.; Eidietis, N. W.
  • Physics of Plasmas, Vol. 17, Issue 5
  • DOI: 10.1063/1.3309426

Demonstration of Tokamak Discharge Shutdown with Shell Pellet Payload Impurity Dispersal
journal, February 2019


Magnetohydrodynamic simulations of massive gas injection into Alcator C-Mod and DIII-D plasmas
journal, May 2008

  • Izzo, V. A.; Whyte, D. G.; Granetz, R. S.
  • Physics of Plasmas, Vol. 15, Issue 5
  • DOI: 10.1063/1.2841526

Impurity mixing and radiation asymmetry in massive gas injection simulations of DIII-D
journal, May 2013


Three-dimensional non-linear magnetohydrodynamic modeling of massive gas injection triggered disruptions in JET
journal, June 2015

  • Fil, A.; Nardon, E.; Hoelzl, M.
  • Physics of Plasmas, Vol. 22, Issue 6
  • DOI: 10.1063/1.4922846

Shattered pellet injection simulations with NIMROD
journal, April 2019

  • Kim, Charlson C.; Liu, Yueqiang; Parks, Paul B.
  • Physics of Plasmas, Vol. 26, Issue 4
  • DOI: 10.1063/1.5088814

Modeling of rapid shutdown in the DIII-D tokamak by core deposition of high-Z material
journal, June 2017

  • Izzo, V. A.; Parks, P. B.
  • Physics of Plasmas, Vol. 24, Issue 6
  • DOI: 10.1063/1.4990447

Nonlinear magnetohydrodynamics simulation using high-order finite elements
journal, March 2004

  • Sovinec, C. R.; Glasser, A. H.; Gianakon, T. A.
  • Journal of Computational Physics, Vol. 195, Issue 1
  • DOI: 10.1016/j.jcp.2003.10.004

The effect of pre-existing islands on disruption mitigation in MHD simulations of DIII-D
journal, May 2017


Momentum-space study of the effect of bremsstrahlung radiation on the energy of runaway electrons in tokamaks
journal, October 2005

  • Bakhtiari, M.; Kramer, G. J.; Whyte, D. G.
  • Physics of Plasmas, Vol. 12, Issue 10
  • DOI: 10.1063/1.2065368

Effect of transonic flow in the ablation cloud on the lifetime of a solid hydrogen pellet in a plasma
journal, January 1978

  • Parks, P. B.; Turnbull, R. J.
  • Physics of Fluids, Vol. 21, Issue 10
  • DOI: 10.1063/1.862088

Neutral gas and plasma shielding scaling law for pellet ablation in Maxwellian plasmas
journal, August 1997


A fast shutdown technique for large tokamaks
journal, May 2000


Emergency discharge quench or rampdown by a noble gas pellet
journal, October 1995


Progress in understanding disruptions triggered by massive gas injection via 3D non-linear MHD modelling with JOREK
journal, October 2016


Axisymmetric benchmarks of impurity dynamics in extended-magnetohydrodynamic simulations
journal, April 2019

  • Lyons, B. C.; Kim, C. C.; Liu, Y. Q.
  • Plasma Physics and Controlled Fusion, Vol. 61, Issue 6
  • DOI: 10.1088/1361-6587/ab0e42

Negative voltage spike in tokamak disruptions
journal, June 1990


Integrated modeling applications for tokamak experiments with OMFIT
journal, July 2015