Reduction of asymmetric wall force in JET and ITER disruptions including runaway electrons

Strauss, H.; Joffrin, E.; Riccardo, V.; Breslau, J.; Paccagnella, R.; Fu, G. Y.

doi:10.1063/1.5129134

Title: Reduction of asymmetric wall force in JET and ITER disruptions including runaway electrons

Abstract

It was shown that asymmetric vertical displacement event (AVDE) disruptions in JET and ITER do not produce a large asymmetric force on conducting structures surrounding the plasma, provided that the current quench (CQ) time is less than the resistive wall penetration time. This is verified with JET data. In ITER the CQ is expected to be comparable to the resistive wall penetration time, which gives a small wall force. It is shown that runaway electrons (REs) in JET do not produce a large wall force, and this is verified with JET data. This occurs if the RE current is about half of the initial plasma current. In ITER, the RE current might be comparable to the initial current, and REs might lengthen the CQ time sufficiently to produce a large wall force.

Authors:

^[1]; Joffrin, E. ^[2];

^[3]; Breslau, J. ^[3];

^[4];

^[5]

HRS Fusion, West Orange, NJ (United States)
Alternative Energies and Atomic Energy Commission (CEA), St. Paul Lez Durance (France). Institute for Magnetic Fusion Research (IRFM)
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Consorzio RFX and Istituto Gas Ionizzati del C.N.R., Padua (Italy)
Zhejiang Univ. of Technology, Hangzhou (China). Institute for Fusion Theory and Simulation (IFTS)

Publication Date:: Wed Feb 12 00:00:00 EST 2020

Research Org.:: HRS Fusion, West Orange, NJ (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Contributing Org.:: Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement No 633053

OSTI Identifier:: 1658456

Alternate Identifier(s):: OSTI ID: 1599248

Grant/Contract Number:: SC0020127; SC0016169; 633053

Resource Type:: Accepted Manuscript

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 27; Journal Issue: 2; Journal ID: ISSN 1070-664X

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ITER; JET; disruptions; wall force; runaway electrons

Citation Formats


                    Strauss, H., Joffrin, E., Riccardo, V., Breslau, J., Paccagnella, R., and Fu, G. Y. Reduction of asymmetric wall force in JET and ITER disruptions including runaway electrons.  United States: N. p., 2020. 
Web.  doi:10.1063/1.5129134.

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                    Strauss, H., Joffrin, E., Riccardo, V., Breslau, J., Paccagnella, R., & Fu, G. Y. Reduction of asymmetric wall force in JET and ITER disruptions including runaway electrons.  United States.  https://doi.org/10.1063/1.5129134

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                    Strauss, H., Joffrin, E., Riccardo, V., Breslau, J., Paccagnella, R., and Fu, G. Y. Wed .  
"Reduction of asymmetric wall force in JET and ITER disruptions including runaway electrons".  United States.  https://doi.org/10.1063/1.5129134.  https://www.osti.gov/servlets/purl/1658456.

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@article{osti_1658456,

  title        = {Reduction of asymmetric wall force in JET and ITER disruptions including runaway electrons},

  author       = {Strauss, H. and Joffrin, E. and Riccardo, V. and Breslau, J. and Paccagnella, R. and Fu, G. Y.},

  abstractNote = {It was shown that asymmetric vertical displacement event (AVDE) disruptions in JET and ITER do not produce a large asymmetric force on conducting structures surrounding the plasma, provided that the current quench (CQ) time is less than the resistive wall penetration time. This is verified with JET data. In ITER the CQ is expected to be comparable to the resistive wall penetration time, which gives a small wall force. It is shown that runaway electrons (REs) in JET do not produce a large wall force, and this is verified with JET data. This occurs if the RE current is about half of the initial plasma current. In ITER, the RE current might be comparable to the initial current, and REs might lengthen the CQ time sufficiently to produce a large wall force.},

  doi          = {10.1063/1.5129134},

  journal      = {Physics of Plasmas},

  number       = 2,

  volume       = 27,

  place        = {United States},

  year         = {Wed Feb 12 00:00:00 EST 2020},

  month        = {Wed Feb 12 00:00:00 EST 2020}

}

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Works referenced in this record:

Plasma current asymmetries during disruptions in JET
journal, April 2014

Gerasimov, S. N.; Hender, T. C.; Morris, J.
Nuclear Fusion, Vol. 54, Issue 7
DOI: 10.1088/0029-5515/54/7/073009

Velocity boundary conditions at a tokamak resistive wall
journal, March 2014

Strauss, H. R.
Physics of Plasmas, Vol. 21, Issue 3
DOI: 10.1063/1.4868436

Resistive stability of a plasma with runaway electrons
journal, December 2007

Helander, P.; Grasso, D.; Hastie, R. J.
Physics of Plasmas, Vol. 14, Issue 12
DOI: 10.1063/1.2817016

Theory for avalanche of runaway electrons in tokamaks
journal, October 1997

Rosenbluth, M. N.; Putvinski, S. V.
Nuclear Fusion, Vol. 37, Issue 10
DOI: 10.1088/0029-5515/37/10/I03

Comparison of JET AVDE disruption data with M3D simulations and implications for ITER
journal, October 2017

Strauss, H.; Joffrin, E.; Riccardo, V.
Physics of Plasmas, Vol. 24, Issue 10
DOI: 10.1063/1.5004692

Wall forces produced during ITER disruptions
journal, August 2010

Strauss, H. R.; Paccagnella, R.; Breslau, J.
Physics of Plasmas, Vol. 17, Issue 8
DOI: 10.1063/1.3474922

Forces between plasma, vessel and TF coils during AVDEs at JET
journal, October 2000

Riccardo, V.; Noll, P.; Walker, S. P.
Nuclear Fusion, Vol. 40, Issue 10
DOI: 10.1088/0029-5515/40/10/311

Runaway electron beam generation and mitigation during disruptions at JET-ILW
journal, August 2015

Reux, C.; Plyusnin, V.; Alper, B.
Nuclear Fusion, Vol. 55, Issue 9
DOI: 10.1088/0029-5515/55/9/093013

Reduction of asymmetric wall force in ITER disruptions with fast current quench
journal, February 2018

Strauss, H.
Physics of Plasmas, Vol. 25, Issue 2
DOI: 10.1063/1.5008813

Plasma simulation studies using multilevel physics models
journal, May 1999

Park, W.; Belova, E. V.; Fu, G. Y.
Physics of Plasmas, Vol. 6, Issue 5
DOI: 10.1063/1.873437

Chapter 3: MHD stability, operational limits and disruptions
journal, June 2007

Hender, T. C.; Wesley, J. C.; Bialek, J.
Nuclear Fusion, Vol. 47, Issue 6
DOI: 10.1088/0029-5515/47/6/S03

Influence of resistive internal kink on runaway current profile
journal, January 2015

Cai, Huishan; Fu, Guoyong
Nuclear Fusion, Vol. 55, Issue 2
DOI: 10.1088/0029-5515/55/2/022001

Sideways wall force produced during tokamak disruptions
journal, June 2013

Strauss, H.; Paccagnella, R.; Breslau, J.
Nuclear Fusion, Vol. 53, Issue 7
DOI: 10.1088/0029-5515/53/7/073018

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Title: Reduction of asymmetric wall force in JET and ITER disruptions including runaway electrons

Abstract

Citation Formats

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