Impurity seeding for suppression of the near scrape-off layer heat flux feature in tokamak limited plasmas

Nespoli, F.; Labit, B.; Furno, I.; Theiler, C.; Sheikh, U. A.; Tsui, C. K.; Boedo, J. A.

doi:10.1063/1.5023201

Title: Impurity seeding for suppression of the near scrape-off layer heat flux feature in tokamak limited plasmas

Abstract

In inboard-limited plasmas, foreseen to be used in future fusion reactor start-up and ramp down phases, the Scrape-Off Layer (SOL) exhibits two regions: the “near” and “far” SOL. The steep radial gradient of the parallel heat flux associated with the near SOL can result in excessive thermal loads onto the solid surfaces, damaging them and/or limiting the operational space of a fusion reactor. In this article, leveraging the results presented in the study by F. Nespoli et al. [Nucl. Fusion 57, 126029 (2017)], we propose a technique for the mitigation and suppression of the near SOL heat flux feature by impurity seeding. Here, the first successful experimental results from the TCV tokamak are presented and discussed.

Authors:

^[1]; Labit, B. ^[1];

^[1];

^[2];

^[3]

Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland). Swiss Plasma Center (SPC)
Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland). Swiss Plasma Center (SPC); Univ. of California-San Diego, La Jolla, CA (United States)
Univ. of California-San Diego, La Jolla, CA (United States)

Publication Date:: 2018-05-01

Research Org.:: Univ. of California, San Diego, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

Contributing Org.:: TCV Team

OSTI Identifier:: 1540175

Alternate Identifier(s):: OSTI ID: 1435485

Grant/Contract Number:: SC0010529

Resource Type:: Accepted Manuscript

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 25; Journal Issue: 5; 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; physics

Citation Formats


                    Nespoli, F., Labit, B., Furno, I., Theiler, C., Sheikh, U. A., Tsui, C. K., and Boedo, J. A. Impurity seeding for suppression of the near scrape-off layer heat flux feature in tokamak limited plasmas.  United States: N. p., 2018. 
Web.  doi:10.1063/1.5023201.

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                    Nespoli, F., Labit, B., Furno, I., Theiler, C., Sheikh, U. A., Tsui, C. K., & Boedo, J. A. Impurity seeding for suppression of the near scrape-off layer heat flux feature in tokamak limited plasmas.  United States.  https://doi.org/10.1063/1.5023201

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                    Nespoli, F., Labit, B., Furno, I., Theiler, C., Sheikh, U. A., Tsui, C. K., and Boedo, J. A. Tue .  
"Impurity seeding for suppression of the near scrape-off layer heat flux feature in tokamak limited plasmas".  United States.  https://doi.org/10.1063/1.5023201.  https://www.osti.gov/servlets/purl/1540175.

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@article{osti_1540175,

  title        = {Impurity seeding for suppression of the near scrape-off layer heat flux feature in tokamak limited plasmas},

  author       = {Nespoli, F. and Labit, B. and Furno, I. and Theiler, C. and Sheikh, U. A. and Tsui, C. K. and Boedo, J. A.},

  abstractNote = {In inboard-limited plasmas, foreseen to be used in future fusion reactor start-up and ramp down phases, the Scrape-Off Layer (SOL) exhibits two regions: the “near” and “far” SOL. The steep radial gradient of the parallel heat flux associated with the near SOL can result in excessive thermal loads onto the solid surfaces, damaging them and/or limiting the operational space of a fusion reactor. In this article, leveraging the results presented in the study by F. Nespoli et al. [Nucl. Fusion 57, 126029 (2017)], we propose a technique for the mitigation and suppression of the near SOL heat flux feature by impurity seeding. Here, the first successful experimental results from the TCV tokamak are presented and discussed.},

  doi          = {10.1063/1.5023201},

  journal      = {Physics of Plasmas},

  number       = 5,

  volume       = 25,

  place        = {United States},

  year         = {2018},

  month        = {5}

}

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Works referenced in this record:

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Works referencing / citing this record:

Numerical estimation of the oxygen impurity transport in the Aditya tokamak
journal, February 2020

Bhattacharya, Amrita; Ghosh, Joydeep; Chowdhuri, M. B.
Physics of Plasmas, Vol. 27, Issue 2
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Similar Records

Title: Impurity seeding for suppression of the near scrape-off layer heat flux feature in tokamak limited plasmas

Abstract

Citation Formats

Scrape-off layer properties of ITER-like limiter start-up plasmas in JET journal, June 2013

Overview of the TCV tokamak program: scientific progress and facility upgrades journal, June 2017

Understanding and suppressing the near scrape-off layer heat flux feature in inboard-limited plasmas in TCV journal, September 2017

Understanding narrow SOL power flux component in COMPASS limiter plasmas by use of Langmuir probes journal, August 2015

Neoclassical conductivity and bootstrap current formulas for general axisymmetric equilibria and arbitrary collisionality regime journal, July 1999

Dynamic fuel retention and release under ITER like wall conditions in JET journal, July 2013

Impact of a narrow limiter SOL heat flux channel on the ITER first wall panel shaping journal, February 2015

In–out impurity density asymmetry in the pedestal region of Alcator C-Mod journal, November 2013

Simulation of plasma current ramp-up with reduced magnetic flux consumption in JT-60SA journal, April 2015

Ohmic flux consumption during initial operation of the NSTX spherical torus journal, September 2001

Poloidal flux linkage requirements for the International Thermonuclear Experimental Reactor journal, August 1994

Heat loads in inboard limited L-mode plasmas in TCV journal, August 2015

Erratum: “Neoclassical conductivity and bootstrap current formulas for general axisymmetric equilibria and arbitrary collisionality regime” [Phys. Plasmas 6 , 2834 (1999)] journal, December 2002

Narrow heat flux channels in the COMPASS limiter scrape-off layer journal, August 2015

Thermal load distribution on the ALT-II limiter of TEXTOR-94 during RI mode operation and during disruptions journal, March 2000

Reduction of poloidal magnetic flux consumption during plasma current ramp-up in DEMO relevant plasma regimes journal, October 2016

Measurement of inner wall limiter SOL widths in KSTAR tokamak journal, August 2017

Tokamak equilibrium reconstruction using Faraday rotation measurements journal, October 1988

Alcator C-Mod: research in support of ITER and steps beyond journal, July 2015

High Confinement and High Density with Stationary Plasma Energy and Strong Edge Radiation in the TEXTOR-94 Tokamak journal, September 1996

Poloidal asymmetry in the narrow heat flux feature in the TCV scrape-off layer journal, June 2017

Scrape-off-layer current loops and floating potential in limited tokamak plasmas journal, December 2017

Partial detachment of high power discharges in ASDEX Upgrade journal, April 2015

Velocity shear, turbulent saturation, and steep plasma gradients in the scrape-off layer of inner-wall limited tokamaks journal, December 2016

Impurity-seeded plasma experiments on JET journal, December 2002

Radiative edges under control by impurity fluxes journal, December 1993

Volt-second analysis and consumption in Doublet III plasmas journal, October 1982

Plasma surface interactions in impurity seeded plasmas journal, August 2011

Hydrogen inventories in nuclear fusion devices journal, March 2001

Power deposition on the DIII-D inner wall limiter journal, August 2015

The Plasma Boundary of Magnetic Fusion Devices journal, January 2001

Velocity shear, turbulent saturation, and steep plasma gradients in the scrape-off layer of inner-wall limited tokamaks text, January 2016

Numerical estimation of the oxygen impurity transport in the Aditya tokamak journal, February 2020

Physics research on the TCV tokamak facility: from conventional to alternative scenarios and beyond journal, August 2019

Scrape-off layer properties of ITER-like limiter start-up plasmas in JET
journal, June 2013

Overview of the TCV tokamak program: scientific progress and facility upgrades
journal, June 2017

Understanding and suppressing the near scrape-off layer heat flux feature in inboard-limited plasmas in TCV
journal, September 2017

Understanding narrow SOL power flux component in COMPASS limiter plasmas by use of Langmuir probes
journal, August 2015

Neoclassical conductivity and bootstrap current formulas for general axisymmetric equilibria and arbitrary collisionality regime
journal, July 1999

Dynamic fuel retention and release under ITER like wall conditions in JET
journal, July 2013

Impact of a narrow limiter SOL heat flux channel on the ITER first wall panel shaping
journal, February 2015

In–out impurity density asymmetry in the pedestal region of Alcator C-Mod
journal, November 2013

Simulation of plasma current ramp-up with reduced magnetic flux consumption in JT-60SA
journal, April 2015

Ohmic flux consumption during initial operation of the NSTX spherical torus
journal, September 2001

Poloidal flux linkage requirements for the International Thermonuclear Experimental Reactor
journal, August 1994

Heat loads in inboard limited L-mode plasmas in TCV
journal, August 2015

Erratum: “Neoclassical conductivity and bootstrap current formulas for general axisymmetric equilibria and arbitrary collisionality regime” [Phys. Plasmas 6 , 2834 (1999)]
journal, December 2002

Narrow heat flux channels in the COMPASS limiter scrape-off layer
journal, August 2015

Thermal load distribution on the ALT-II limiter of TEXTOR-94 during RI mode operation and during disruptions
journal, March 2000

Reduction of poloidal magnetic flux consumption during plasma current ramp-up in DEMO relevant plasma regimes
journal, October 2016

Measurement of inner wall limiter SOL widths in KSTAR tokamak
journal, August 2017

Tokamak equilibrium reconstruction using Faraday rotation measurements
journal, October 1988

Alcator C-Mod: research in support of ITER and steps beyond
journal, July 2015

High Confinement and High Density with Stationary Plasma Energy and Strong Edge Radiation in the TEXTOR-94 Tokamak
journal, September 1996

Poloidal asymmetry in the narrow heat flux feature in the TCV scrape-off layer
journal, June 2017

Scrape-off-layer current loops and floating potential in limited tokamak plasmas
journal, December 2017

Partial detachment of high power discharges in ASDEX Upgrade
journal, April 2015

Velocity shear, turbulent saturation, and steep plasma gradients in the scrape-off layer of inner-wall limited tokamaks
journal, December 2016

Impurity-seeded plasma experiments on JET
journal, December 2002

Radiative edges under control by impurity fluxes
journal, December 1993

Volt-second analysis and consumption in Doublet III plasmas
journal, October 1982

Plasma surface interactions in impurity seeded plasmas
journal, August 2011

Hydrogen inventories in nuclear fusion devices
journal, March 2001

Power deposition on the DIII-D inner wall limiter
journal, August 2015

The Plasma Boundary of Magnetic Fusion Devices
journal, January 2001

Velocity shear, turbulent saturation, and steep plasma gradients in the scrape-off layer of inner-wall limited tokamaks
text, January 2016

Numerical estimation of the oxygen impurity transport in the Aditya tokamak
journal, February 2020

Physics research on the TCV tokamak facility: from conventional to alternative scenarios and beyond
journal, August 2019