Results from core-edge experiments in high Power, high performance plasmas on DIII-D

Petrie, T. W.; Fenstermacher, M. E.; Holcomb, C. T.; Osborne, T. H.; Allen, S. L.; Ferron, J. R.; Guo, H. Y.; Lasnier, C. J.; Leonard, A. W.; Luce, T. C.; Makowski, M. A.; McLean, A. G.; Pace, D. C.; Solomon, W. M.; Turco, F.; VanZeeland, M. A.; Watkins, J. G.

doi:10.1016/j.nme.2016.10.029

Title: Results from core-edge experiments in high Power, high performance plasmas on DIII-D

Abstract

Here, significant challenges to reducing divertor heat flux in highly powered near-double null divertor (DND) hybrid plasmas, while still maintaining both high performance metrics and low enough density for application of RF heating, are identified. For these DNDs on DIII-D, the scaling of the peak heat flux at the outer target (q_⊥^P) ∝ [P_SOL x I_P]^0.92 for P_SOL = 8-19 MW and I_P = 1.0–1.4 MA, and is consistent with standard ITPA scaling for single-null H-mode plasmas. Two divertor heat flux reduction methods were tested. First, applying the puff-and-pump radiating divertor to DIII-D plasmas may be problematical at high power and H98 (≥ 1.5) due to improvement in confinement time with deuterium gas puffing which can lead to unacceptably high core density under certain conditions. Second, q_⊥^P for these high performance DNDs was reduced by ≈35% when an open divertor is closed on the common flux side of the outer divertor target (“semi-slot”) but also that heating near the slot opening is a significant source for impurity contamination of the core.

Authors:

^[1]; Fenstermacher, M. E. ^[2]; Holcomb, C. T. ^[2]; Osborne, T. H. ^[1]; Allen, S. L. ^[2]; Ferron, J. R. ^[1]; Guo, H. Y. ^[1]; Lasnier, C. J. ^[2]; Leonard, A. W. ^[1]; Luce, T. C. ^[1]; Makowski, M. A. ^[2]; McLean, A. G. ^[2];

^[1]; Solomon, W. M. ^[1]; Turco, F. ^[3]; VanZeeland, M. A. ^[1]; Watkins, J. G. ^[4]

General Atomics, San Diego, CA (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Columbia Univ., New York, NY (United States)
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Sat Dec 24 00:00:00 EST 2016

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); General Atomics, San Diego, CA (United States)

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

Contributing Org.:: Lawrence Livermore National Laboratory, Livermore, California, USA Columbia University, New York, New York, USA Sandia National Laboratories, Albuquerque, New Mexico, USA

OSTI Identifier:: 1474338

Alternate Identifier(s):: OSTI ID: 1372094

Report Number(s):: LLNL-JRNL-752185
Journal ID: ISSN 2352-1791; 930435

Grant/Contract Number:: AC52-07NA27344; FC02-04ER54698

Resource Type:: Accepted Manuscript

Journal Name:: Nuclear Materials and Energy

Additional Journal Information:: Journal Volume: 12; Journal Issue: C; Journal ID: ISSN 2352-1791

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DIII-D; divertor geometry; gas injection and fueling; impurity sources; power deposition

Citation Formats


                    Petrie, T. W., Fenstermacher, M. E., Holcomb, C. T., Osborne, T. H., Allen, S. L., Ferron, J. R., Guo, H. Y., Lasnier, C. J., Leonard, A. W., Luce, T. C., Makowski, M. A., McLean, A. G., Pace, D. C., Solomon, W. M., Turco, F., VanZeeland, M. A., and Watkins, J. G. Results from core-edge experiments in high Power, high performance plasmas on DIII-D.  United States: N. p., 2016. 
Web.  doi:10.1016/j.nme.2016.10.029.

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                    Petrie, T. W., Fenstermacher, M. E., Holcomb, C. T., Osborne, T. H., Allen, S. L., Ferron, J. R., Guo, H. Y., Lasnier, C. J., Leonard, A. W., Luce, T. C., Makowski, M. A., McLean, A. G., Pace, D. C., Solomon, W. M., Turco, F., VanZeeland, M. A., & Watkins, J. G. Results from core-edge experiments in high Power, high performance plasmas on DIII-D.  United States.  https://doi.org/10.1016/j.nme.2016.10.029

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                    Petrie, T. W., Fenstermacher, M. E., Holcomb, C. T., Osborne, T. H., Allen, S. L., Ferron, J. R., Guo, H. Y., Lasnier, C. J., Leonard, A. W., Luce, T. C., Makowski, M. A., McLean, A. G., Pace, D. C., Solomon, W. M., Turco, F., VanZeeland, M. A., and Watkins, J. G. Sat .  
"Results from core-edge experiments in high Power, high performance plasmas on DIII-D".  United States.  https://doi.org/10.1016/j.nme.2016.10.029.  https://www.osti.gov/servlets/purl/1474338.

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@article{osti_1474338,

  title        = {Results from core-edge experiments in high Power, high performance plasmas on DIII-D},

  author       = {Petrie, T. W. and Fenstermacher, M. E. and Holcomb, C. T. and Osborne, T. H. and Allen, S. L. and Ferron, J. R. and Guo, H. Y. and Lasnier, C. J. and Leonard, A. W. and Luce, T. C. and Makowski, M. A. and McLean, A. G. and Pace, D. C. and Solomon, W. M. and Turco, F. and VanZeeland, M. A. and Watkins, J. G.},

  abstractNote = {Here, significant challenges to reducing divertor heat flux in highly powered near-double null divertor (DND) hybrid plasmas, while still maintaining both high performance metrics and low enough density for application of RF heating, are identified. For these DNDs on DIII-D, the scaling of the peak heat flux at the outer target (q⊥P) ∝ [PSOL x IP]0.92 for PSOL = 8-19 MW and IP = 1.0–1.4 MA, and is consistent with standard ITPA scaling for single-null H-mode plasmas. Two divertor heat flux reduction methods were tested. First, applying the puff-and-pump radiating divertor to DIII-D plasmas may be problematical at high power and H98 (≥ 1.5) due to improvement in confinement time with deuterium gas puffing which can lead to unacceptably high core density under certain conditions. Second, q⊥P for these high performance DNDs was reduced by ≈35% when an open divertor is closed on the common flux side of the outer divertor target (“semi-slot”) but also that heating near the slot opening is a significant source for impurity contamination of the core.},

  doi          = {10.1016/j.nme.2016.10.029},

  journal      = {Nuclear Materials and Energy},

  number       = C,

  volume       = 12,

  place        = {United States},

  year         = {Sat Dec 24 00:00:00 EST 2016},

  month        = {Sat Dec 24 00:00:00 EST 2016}

}

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Works referenced in this record:

Impurity enrichment studies with induced scrape-off layer flow on DIII-D
journal, December 1998

Wade, M. R.; Hogan, J. T.; Allen, S. L.
Nuclear Fusion, Vol. 38, Issue 12
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Impurity compression and enrichment studies on Alcator C-Mod
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Goetz, J. A.; Lipschultz, B.; Pitcher, C. S.
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Integrated exhaust control with divertor parameter feedback and pellet ELM pacemaking in ASDEX Upgrade
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Kallenbach, A.; Lang, P. T.; Dux, R.
Journal of Nuclear Materials, Vol. 337-339
DOI: 10.1016/j.jnucmat.2004.10.027

Compatibility of the radiating divertor with high performance plasmas in DIII-D
journal, June 2007

Petrie, T. W.; Wade, M. R.; Brooks, N. H.
Journal of Nuclear Materials, Vol. 363-365
DOI: 10.1016/j.jnucmat.2007.01.131

Application of the radiating divertor approach to innovative tokamak divertor concepts
journal, August 2015

Petrie, T. W.; Allen, S. L.; Fenstermacher, M. E.
Journal of Nuclear Materials, Vol. 463
DOI: 10.1016/j.jnucmat.2014.11.008

Effect of changes in separatrix magnetic geometry on divertor behaviour in DIII-D
journal, September 2013

Petrie, T. W.; Canik, J. M.; Lasnier, C. J.
Nuclear Fusion, Vol. 53, Issue 11
DOI: 10.1088/0029-5515/53/11/113024

Snowflake divertor configuration studies in National Spherical Torus Experiment
journal, August 2012

Soukhanovskii, V. A.; Bell, R. E.; Diallo, A.
Physics of Plasmas, Vol. 19, Issue 8
DOI: 10.1063/1.4737117

On heat loading, novel divertors, and fusion reactors
journal, July 2007

Kotschenreuther, M.; Valanju, P. M.; Mahajan, S. M.
Physics of Plasmas, Vol. 14, Issue 7
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Changes in edge and scrape-off layer plasma behavior due to variation in magnetic balance in DIII-D
journal, March 2003

Petrie, T.; Watkins, J.; Baylor, L.
Journal of Nuclear Materials, Vol. 313-316
DOI: 10.1016/S0022-3115(02)01459-9

Scaling of the tokamak near the scrape-off layer H-mode power width and implications for ITER
journal, August 2013

Eich, T.; Leonard, A. W.; Pitts, R. A.
Nuclear Fusion, Vol. 53, Issue 9
DOI: 10.1088/0029-5515/53/9/093031

Compatibility of detached divertor operation with robust edge pedestal performance
journal, August 2015

Leonard, A. W.; Makowski, M. A.; McLean, A. G.
Journal of Nuclear Materials, Vol. 463
DOI: 10.1016/j.jnucmat.2014.11.007

Edge localized modes and the pedestal: A model based on coupled peeling–ballooning modes
journal, May 2002

Snyder, P. B.; Wilson, H. R.; Ferron, J. R.
Physics of Plasmas, Vol. 9, Issue 5
DOI: 10.1063/1.1449463

Works referencing / citing this record:

High performance double-null plasmas under radiating divertor and mantle scenarios on DIII-D
journal, July 2019

Petrie, T. W.; Grierson, B. A.; Osborne, T.
Nuclear Fusion, Vol. 59, Issue 8
DOI: 10.1088/1741-4326/ab2936

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Title: Results from core-edge experiments in high Power, high performance plasmas on DIII-D

Abstract

Citation Formats

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Impurity compression and enrichment studies on Alcator C-Mod
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