Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges

Maingi, Rajesh; Osborne, T. H.; Bell, M. G.; Bell, R. E.; Boyle, D. P.; Canik, John M.; Diallo, A.; Kaita, R.; Kaye, S. M.; Kugel, H. W.; LeBlanc, B. P.; Sabbagh, S. A.; Skinner, C. H.; Soukhanovskii, V. A.

doi:10.1016/j.jnucmat.2014.10.084

Title: Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges

Abstract

In this paper, the effects of a pre-discharge lithium evaporation variation on highly shaped discharges in the National Spherical Torus Experiment (NSTX) are documented. Lithium wall conditioning ('dose') was routinely applied onto graphite plasma facing components between discharges in NSTX, partly to reduce recycling. Reduced D-alpha, emission from the lower and upper divertor and center stack was observed, as well as reduced midplane neutral pressure; the magnitude of reduction increased with the pre-discharge lithium dose. Improved energy confinement, both raw tau(E) and H-factor normalized to scalings, with increasing lithium dose was also observed. At the highest doses, we also observed elimination of edge-localized modes. The midplane edge plasma profiles were dramatically altered, comparable to lithium dose scans at lower shaping, where the strike point was farther from the lithium deposition centroid. This indicates that the benefits of lithium conditioning should apply to the highly shaped plasmas planned in NSTX-U. (C) 2014 Elsevier B.V. All rights reserved.

Authors:

Maingi, Rajesh ^[1]; Osborne, T. H. ^[2]; Bell, M. G. ^[1]; Bell, R. E. ^[1]; Boyle, D. P. ^[1]; Canik, John M. ^[3]; Diallo, A. ^[1]; Kaita, R. ^[1]; Kaye, S. M. ^[1]; Kugel, H. W. ^[1]; LeBlanc, B. P. ^[1]; Sabbagh, S. A. ^[4]; Skinner, C. H. ^[1]; Soukhanovskii, V. A. ^[5]

Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
General Atomics, San Diego, CA (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Columbia Univ., New York, NY (United States). Applied Physics and Applied Math Dept.
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: Tue Nov 04 00:00:00 EST 2014

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

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

OSTI Identifier:: 1341539

Alternate Identifier(s):: OSTI ID: 1260716; OSTI ID: 1281680

Report Number(s):: LLNL-JRNL-696263
Journal ID: ISSN 0022-3115; AT1030100; ERAT021

Grant/Contract Number:: AC05-00OR22725; AC02-09CH11466; FC02-04ER54698; FC02-99ER54512; AC52-07NA27344

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Nuclear Materials

Additional Journal Information:: Journal Volume: 463; Journal Issue: C; Journal ID: ISSN 0022-3115

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 70 PLASMA PHYSICS AND FUSION

Citation Formats


                    Maingi, Rajesh, Osborne, T. H., Bell, M. G., Bell, R. E., Boyle, D. P., Canik, John M., Diallo, A., Kaita, R., Kaye, S. M., Kugel, H. W., LeBlanc, B. P., Sabbagh, S. A., Skinner, C. H., and Soukhanovskii, V. A. Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges.  United States: N. p., 2014. 
Web.  doi:10.1016/j.jnucmat.2014.10.084.

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                    Maingi, Rajesh, Osborne, T. H., Bell, M. G., Bell, R. E., Boyle, D. P., Canik, John M., Diallo, A., Kaita, R., Kaye, S. M., Kugel, H. W., LeBlanc, B. P., Sabbagh, S. A., Skinner, C. H., & Soukhanovskii, V. A. Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges.  United States.  https://doi.org/10.1016/j.jnucmat.2014.10.084

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                    Maingi, Rajesh, Osborne, T. H., Bell, M. G., Bell, R. E., Boyle, D. P., Canik, John M., Diallo, A., Kaita, R., Kaye, S. M., Kugel, H. W., LeBlanc, B. P., Sabbagh, S. A., Skinner, C. H., and Soukhanovskii, V. A. Tue .  
"Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges".  United States.  https://doi.org/10.1016/j.jnucmat.2014.10.084.  https://www.osti.gov/servlets/purl/1341539.

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@article{osti_1341539,

  title        = {Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges},

  author       = {Maingi, Rajesh and Osborne, T. H. and Bell, M. G. and Bell, R. E. and Boyle, D. P. and Canik, John M. and Diallo, A. and Kaita, R. and Kaye, S. M. and Kugel, H. W. and LeBlanc, B. P. and Sabbagh, S. A. and Skinner, C. H. and Soukhanovskii, V. A.},

  abstractNote = {In this paper, the effects of a pre-discharge lithium evaporation variation on highly shaped discharges in the National Spherical Torus Experiment (NSTX) are documented. Lithium wall conditioning ('dose') was routinely applied onto graphite plasma facing components between discharges in NSTX, partly to reduce recycling. Reduced D-alpha, emission from the lower and upper divertor and center stack was observed, as well as reduced midplane neutral pressure; the magnitude of reduction increased with the pre-discharge lithium dose. Improved energy confinement, both raw tau(E) and H-factor normalized to scalings, with increasing lithium dose was also observed. At the highest doses, we also observed elimination of edge-localized modes. The midplane edge plasma profiles were dramatically altered, comparable to lithium dose scans at lower shaping, where the strike point was farther from the lithium deposition centroid. This indicates that the benefits of lithium conditioning should apply to the highly shaped plasmas planned in NSTX-U. (C) 2014 Elsevier B.V. All rights reserved.},

  doi          = {10.1016/j.jnucmat.2014.10.084},

  journal      = {Journal of Nuclear Materials},

  number       = C,

  volume       = 463,

  place        = {United States},

  year         = {Tue Nov 04 00:00:00 EST 2014},

  month        = {Tue Nov 04 00:00:00 EST 2014}

}

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Works referenced in this record:

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Mansfield, D. K.; Johnson, D. W.; Grek, B.
Nuclear Fusion, Vol. 41, Issue 12
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Enhanced Energy Confinement and Performance in a Low-Recycling Tokamak
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Edge transport and turbulence reduction with lithium coated plasma facing components in the National Spherical Torus Experiment
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Canik, J. M.; Maingi, R.; Kubota, S.
Physics of Plasmas, Vol. 18, Issue 5
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The relationships between edge localized modes suppression, pedestal profiles and lithium wall coatings in NSTX
journal, September 2011

Boyle, D. P.; Maingi, R.; Snyder, P. B.
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The effect of progressively increasing lithium coatings on plasma discharge characteristics, transport, edge profiles and ELM stability in the National Spherical Torus Experiment
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Effect of plasma shaping on performance in the National Spherical Torus Experiment
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Overview of the physics and engineering design of NSTX upgrade
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Exploration of the equilibrium operating space for NSTX-Upgrade
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Gerhardt, S. P.; Andre, R.; Menard, J. E.
Nuclear Fusion, Vol. 52, Issue 8
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Evaporated lithium surface coatings in NSTX
journal, June 2009

Kugel, H. W.; Mansfield, D.; Maingi, R.
Journal of Nuclear Materials, Vol. 390-391
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The effect of lithium surface coatings on plasma performance in the National Spherical Torus Experiment
journal, May 2008

Kugel, H. W.; Bell, M. G.; Ahn, J. -W.
Physics of Plasmas, Vol. 15, Issue 5
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Plasma response to lithium-coated plasma-facing components in the National Spherical Torus Experiment
journal, November 2009

Bell, M. G.; Kugel, H. W.; Kaita, R.
Plasma Physics and Controlled Fusion, Vol. 51, Issue 12
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Characteristics of energy transport of Li-conditioned and non-Li-conditioned plasmas in the National Spherical Torus Experiment (NSTX)
journal, November 2009

Ding, S.; Kaye, S. M.; Bell, R. E.
Plasma Physics and Controlled Fusion, Vol. 52, Issue 1
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The dependence of H-mode energy confinement and transport on collisionality in NSTX
journal, April 2013

Kaye, S. M.; Gerhardt, S.; Guttenfelder, W.
Nuclear Fusion, Vol. 53, Issue 6
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Transition to ELM-free improved H-mode by lithium deposition on NSTX graphite divertor surfaces
journal, June 2009

Mansfield, D. K.; Kugel, H. W.; Maingi, R.
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Multi-Fluid Modeling of Low-Recycling Divertor Regimes
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Contributions to Plasma Physics, Vol. 50, Issue 3-5
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Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX
journal, August 2011

Canik, J. M.; Maingi, R.; Soukhanovskii, V. A.
Journal of Nuclear Materials, Vol. 415, Issue 1
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Varying the pre-discharge lithium wall coatings to alter the characteristics of the ELM-free H-mode pedestal in NSTX
journal, July 2013

Boyle, D. P.; Canik, J. M.; Maingi, R.
Journal of Nuclear Materials, Vol. 438
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Surface chemistry analysis of lithium conditioned NSTX graphite tiles correlated to plasma performance
journal, December 2013

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Works referencing / citing this record:

Gyrokinetic neoclassical study of the bootstrap current in the tokamak edge pedestal with fully non-linear Coulomb collisions
journal, April 2016

Hager, Robert; Chang, C. S.
Physics of Plasmas, Vol. 23, Issue 4
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Scenario development during commissioning operations on the National Spherical Torus Experiment Upgrade
journal, February 2018

Battaglia, D. J.; Boyer, M. D.; Gerhardt, S.
Nuclear Fusion, Vol. 58, Issue 4
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Linear gyrokinetic simulations of microinstabilities within the pedestal region of H-mode NSTX discharges in a highly shaped geometry
journal, June 2016

Coury, M.; Guttenfelder, W.; Mikkelsen, D. R.
Physics of Plasmas, Vol. 23, Issue 6
DOI: 10.1063/1.4954911

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Similar Records

Title: Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges

Abstract

Citation Formats

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

First experiments with lithium limiter on FTU journal, June 2007

Impact of lithium-coated walls on plasma performance in the TJ-II stellarator journal, June 2009

Approaches towards long-pulse divertor operations on EAST by active control of plasma–wall interactions journal, November 2013

Edge transport and turbulence reduction with lithium coated plasma facing components in the National Spherical Torus Experiment journal, May 2011

The relationships between edge localized modes suppression, pedestal profiles and lithium wall coatings in NSTX journal, September 2011

The effect of progressively increasing lithium coatings on plasma discharge characteristics, transport, edge profiles and ELM stability in the National Spherical Torus Experiment journal, June 2012

Effect of plasma shaping on performance in the National Spherical Torus Experiment journal, May 2006

Overview of the physics and engineering design of NSTX upgrade journal, July 2012

Exploration of the equilibrium operating space for NSTX-Upgrade journal, August 2012

Evaporated lithium surface coatings in NSTX journal, June 2009

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

Plasma response to lithium-coated plasma-facing components in the National Spherical Torus Experiment journal, November 2009

Characteristics of energy transport of Li-conditioned and non-Li-conditioned plasmas in the National Spherical Torus Experiment (NSTX) journal, November 2009

The dependence of H-mode energy confinement and transport on collisionality in NSTX journal, April 2013

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

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

Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX journal, August 2011

Varying the pre-discharge lithium wall coatings to alter the characteristics of the ELM-free H-mode pedestal in NSTX journal, July 2013

Surface chemistry analysis of lithium conditioned NSTX graphite tiles correlated to plasma performance journal, December 2013

ITER L mode confinement database journal, September 1997

Scaling studies of the high mode pedestal journal, May 1998

Edge microstability of NSTX plasmas without and with lithium-coated plasma-facing components journal, September 2013

Gyrokinetic neoclassical study of the bootstrap current in the tokamak edge pedestal with fully non-linear Coulomb collisions journal, April 2016

Scenario development during commissioning operations on the National Spherical Torus Experiment Upgrade journal, February 2018

Linear gyrokinetic simulations of microinstabilities within the pedestal region of H-mode NSTX discharges in a highly shaped geometry journal, June 2016

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

First experiments with lithium limiter on FTU
journal, June 2007

Impact of lithium-coated walls on plasma performance in the TJ-II stellarator
journal, June 2009

Approaches towards long-pulse divertor operations on EAST by active control of plasma–wall interactions
journal, November 2013

Edge transport and turbulence reduction with lithium coated plasma facing components in the National Spherical Torus Experiment
journal, May 2011

The relationships between edge localized modes suppression, pedestal profiles and lithium wall coatings in NSTX
journal, September 2011

The effect of progressively increasing lithium coatings on plasma discharge characteristics, transport, edge profiles and ELM stability in the National Spherical Torus Experiment
journal, June 2012

Effect of plasma shaping on performance in the National Spherical Torus Experiment
journal, May 2006

Overview of the physics and engineering design of NSTX upgrade
journal, July 2012

Exploration of the equilibrium operating space for NSTX-Upgrade
journal, August 2012

Evaporated lithium surface coatings in NSTX
journal, June 2009

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

Plasma response to lithium-coated plasma-facing components in the National Spherical Torus Experiment
journal, November 2009

Characteristics of energy transport of Li-conditioned and non-Li-conditioned plasmas in the National Spherical Torus Experiment (NSTX)
journal, November 2009

The dependence of H-mode energy confinement and transport on collisionality in NSTX
journal, April 2013

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

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

Measurements and 2-D modeling of recycling and edge transport in discharges with lithium-coated PFCs in NSTX
journal, August 2011

Varying the pre-discharge lithium wall coatings to alter the characteristics of the ELM-free H-mode pedestal in NSTX
journal, July 2013

Surface chemistry analysis of lithium conditioned NSTX graphite tiles correlated to plasma performance
journal, December 2013

ITER L mode confinement database
journal, September 1997

Scaling studies of the high mode pedestal
journal, May 1998

Edge microstability of NSTX plasmas without and with lithium-coated plasma-facing components
journal, September 2013

Gyrokinetic neoclassical study of the bootstrap current in the tokamak edge pedestal with fully non-linear Coulomb collisions
journal, April 2016

Scenario development during commissioning operations on the National Spherical Torus Experiment Upgrade
journal, February 2018

Linear gyrokinetic simulations of microinstabilities within the pedestal region of H-mode NSTX discharges in a highly shaped geometry
journal, June 2016