Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX

Canik, J. M.; Maingi, R.; Soukhanovskii, V. A.; Bell, R. E.; Kugel, H. W.; LeBlanc, B. P.; Osborne, T. H.

doi:10.1016/j.jnucmat.2010.11.084

Title: Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX

Abstract

We report the application of lithium coatings on plasma facing components has been shown to profoundly affect plasma performance in the National Spherical Torus Experiment, improving energy confinement and eliminating edge-localized modes. The edge particle balance during these ELM-free discharges has been studied through 2-D plasma-neutrals modeling, constrained by measurements of the upstream plasma density and temperature profiles and the divertor heat flux and $$\mathcal{D}_α$$ emission. The calculations indicate that the reduction in divertor $$\mathcal{D}_α$$ emission with lithium coatings applied is consistent with a drop in recycling coefficient from $$\mathcal{R}$$ ~ 0.98 to $$\mathcal{R}$$ ~ 0.9. The change in recycling is not sufficient to account for the change in edge density profiles: interpretive modeling indicates similar transport coefficients within the edge transport barrier ($$D/χ_e$$ ~ 0.2/1.0 m²/s), but a widening of the barrier with lithium.

Authors:

Canik, J. M. ^[1]; Maingi, R. ^[1]; Soukhanovskii, V. A. ^[2]; Bell, R. E. ^[3]; Kugel, H. W. ^[3]; LeBlanc, B. P. ^[3]; Osborne, T. H. ^[4]

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
General Atomics, San Diego, CA (United States)

Publication Date:: Thu Dec 02 00:00:00 EST 2010

Research Org.:: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1898299

Report Number(s):: LLNL-JRNL-434280
Journal ID: ISSN 0022-3115; 402094; TRN: US2310875

Grant/Contract Number:: AC52-07NA27344; AC05-00OR22725; AC02-09CH11466; FC02-04ER54698

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Nuclear Materials

Additional Journal Information:: Journal Volume: 415; Journal Issue: 1; Journal ID: ISSN 0022-3115

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; plasma-materials interaction; plasma properties; lithium; cross-field transport; edge molding; NSTX

Citation Formats


                    Canik, J. M., Maingi, R., Soukhanovskii, V. A., Bell, R. E., Kugel, H. W., LeBlanc, B. P., and Osborne, T. H. Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX.  United States: N. p., 2010. 
Web.  doi:10.1016/j.jnucmat.2010.11.084.

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                    Canik, J. M., Maingi, R., Soukhanovskii, V. A., Bell, R. E., Kugel, H. W., LeBlanc, B. P., & Osborne, T. H. Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX.  United States.  https://doi.org/10.1016/j.jnucmat.2010.11.084

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                    Canik, J. M., Maingi, R., Soukhanovskii, V. A., Bell, R. E., Kugel, H. W., LeBlanc, B. P., and Osborne, T. H. Thu .  
"Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX".  United States.  https://doi.org/10.1016/j.jnucmat.2010.11.084.  https://www.osti.gov/servlets/purl/1898299.

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@article{osti_1898299,

  title        = {Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX},

  author       = {Canik, J. M. and Maingi, R. and Soukhanovskii, V. A. and Bell, R. E. and Kugel, H. W. and LeBlanc, B. P. and Osborne, T. H.},

  abstractNote = {We report the application of lithium coatings on plasma facing components has been shown to profoundly affect plasma performance in the National Spherical Torus Experiment, improving energy confinement and eliminating edge-localized modes. The edge particle balance during these ELM-free discharges has been studied through 2-D plasma-neutrals modeling, constrained by measurements of the upstream plasma density and temperature profiles and the divertor heat flux and $\mathcal{D}_α$ emission. The calculations indicate that the reduction in divertor $\mathcal{D}_α$ emission with lithium coatings applied is consistent with a drop in recycling coefficient from $\mathcal{R}$ ~ 0.98 to $\mathcal{R}$ ~ 0.9. The change in recycling is not sufficient to account for the change in edge density profiles: interpretive modeling indicates similar transport coefficients within the edge transport barrier ($D/χ_e$ ~ 0.2/1.0 m2/s), but a widening of the barrier with lithium.},

  doi          = {10.1016/j.jnucmat.2010.11.084},

  journal      = {Journal of Nuclear Materials},

  number       = 1,

  volume       = 415,

  place        = {United States},

  year         = {Thu Dec 02 00:00:00 EST 2010},

  month        = {Thu Dec 02 00:00:00 EST 2010}

}

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Similar Records

Title: Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX

Abstract

Citation Formats

Ignited spherical tokamaks and plasma regimes with LiWalls journal, November 2004

Radiative Divertor Modelling for ITER and TPX journal, January 1996

The effect of lithium surface coatings on plasma performance in the National Spherical Torus Experiment journal, May 2008

Transition to ELM-free improved H-mode by lithium deposition on NSTX graphite divertor surfaces journal, June 2009

Infrared camera diagnostic for heat flux measurements on the National Spherical Torus Experiment journal, December 2003

SOLPS modelling of ASDEX upgrade H-mode plasma journal, May 2006

Multi-Fluid Modeling of Low-Recycling Divertor Regimes journal, May 2010

Exploration of spherical torus physics in the NSTX device journal, March 2000

Edge-Localized-Mode Suppression through Density-Profile Modification with Lithium-Wall Coatings in the National Spherical Torus Experiment journal, August 2009

Particle control in steady state magnetic fusion reactors by solid and liquid lithium plasma-facing components journal, February 2006

High-resolution spectroscopic diagnostic for divertor and scrape-off layer neutral and impurity emission measurements in the National Spherical Torus Experiment journal, March 2003

Divertor heat flux scaling with heating power and plasma current in H-mode discharges in the national spherical torus experiment journal, June 2007

Observations concerning the injection of a lithium aerosol into the edge of TFTR discharges journal, December 2001

Enhanced Energy Confinement and Performance in a Low-Recycling Tokamak journal, August 2006

Effect of lithium PFC coatings on NSTX density control journal, June 2007

H-mode pedestal, ELM and power threshold studies in NSTX journal, August 2005

Low recycling and high power density handling physics in the Current Drive Experiment-Upgrade with lithium plasma-facing components journal, May 2007

ALPS–advanced limiter-divertor plasma-facing systems journal, November 2000

Active particle control in the CPD compact spherical tokamak by a lithium-gettered rotating drum limiter journal, June 2009

Scaling studies of the high mode pedestal journal, May 1998

Plasma Edge Physics with B2-Eirene journal, February 2006

Core fueling and edge particle flux analysis in ohmically and auxiliary heated NSTX plasmas journal, March 2003

Ignited spherical tokamaks and plasma regimes with LiWalls
journal, November 2004

Radiative Divertor Modelling for ITER and TPX
journal, January 1996

The effect of lithium surface coatings on plasma performance in the National Spherical Torus Experiment
journal, May 2008

Transition to ELM-free improved H-mode by lithium deposition on NSTX graphite divertor surfaces
journal, June 2009

Infrared camera diagnostic for heat flux measurements on the National Spherical Torus Experiment
journal, December 2003

SOLPS modelling of ASDEX upgrade H-mode plasma
journal, May 2006

Multi-Fluid Modeling of Low-Recycling Divertor Regimes
journal, May 2010

Exploration of spherical torus physics in the NSTX device
journal, March 2000

Edge-Localized-Mode Suppression through Density-Profile Modification with Lithium-Wall Coatings in the National Spherical Torus Experiment
journal, August 2009

Particle control in steady state magnetic fusion reactors by solid and liquid lithium plasma-facing components
journal, February 2006

High-resolution spectroscopic diagnostic for divertor and scrape-off layer neutral and impurity emission measurements in the National Spherical Torus Experiment
journal, March 2003

Divertor heat flux scaling with heating power and plasma current in H-mode discharges in the national spherical torus experiment
journal, June 2007

Observations concerning the injection of a lithium aerosol into the edge of TFTR discharges
journal, December 2001

Enhanced Energy Confinement and Performance in a Low-Recycling Tokamak
journal, August 2006

Effect of lithium PFC coatings on NSTX density control
journal, June 2007

H-mode pedestal, ELM and power threshold studies in NSTX
journal, August 2005

Low recycling and high power density handling physics in the Current Drive Experiment-Upgrade with lithium plasma-facing components
journal, May 2007

ALPS–advanced limiter-divertor plasma-facing systems
journal, November 2000

Active particle control in the CPD compact spherical tokamak by a lithium-gettered rotating drum limiter
journal, June 2009

Scaling studies of the high mode pedestal
journal, May 1998

Plasma Edge Physics with B2-Eirene
journal, February 2006

Core fueling and edge particle flux analysis in ohmically and auxiliary heated NSTX plasmas
journal, March 2003