Achievement of Reactor-Relevant Performance in Negative Triangularity Shape in the DIII-D Tokamak

Austin, M. E.; Marinoni, A.; Walker, M. L.; Brookman, M. W.; deGrassie, J. S.; Hyatt, A. W.; McKee, G. R.; Petty, C. C.; Rhodes, T. L.; Smith, S. P.; Sung, C.; Thome, K. E.; Turnbull, A. D.

doi:10.7910/DVN/D79LV8

Title: Achievement of Reactor-Relevant Performance in Negative Triangularity Shape in the DIII-D Tokamak

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Abstract

Plasma discharges with a negative triangularity (δ=−0.4) shape have been created in the DIII-D tokamak with a significant normalized beta (βN=2.7) and confinement characteristic of the high confinement mode (H98y2=1.2) despite the absence of an edge pressure pedestal and no edge localized modes (ELMs). These inner-wall-limited plasmas have a similar global performance as a positive triangularity (δ=+0.4) ELMing H-mode discharge with the same plasma current, elongation and cross sectional area. For cases both of dominant electron cyclotron heating with Te/Ti>1 and dominant neutral beam injection heating with Te/Ti=1, turbulent fluctuations over radii 0.5<ρ<0.9 were reduced by 10–50% in the negative triangularity shape compared to the matching positive triangularity shape, depending on the radius and conditions.

Authors:

Austin, M. E.; Marinoni, A.; Walker, M. L.; Brookman, M. W.; deGrassie, J. S.; Hyatt, A. W.; McKee, G. R.; Petty, C. C.; Rhodes, T. L.; Smith, S. P.; Sung, C.; Thome, K. E.; Turnbull, A. D.

OSTI

Publication Date:: Wed May 05 00:00:00 EDT 2021

DOE Contract Number:: FC02-04ER54698; FG02-97ER54415; FG02-94ER54235; FG02-08ER54984; FG02-08ER54999; AC52-07NA27344

Research Org.:: General Atomics, San Diego, CA (United States); Univ. of Texas, Austin, TX (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Univ. of California, Los Angeles, CA (United States); Univ. of Wisconsin, Madison, WI (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES); USDOE National Nuclear Security Administration (NNSA)

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

OSTI Identifier:: 1882406

DOI:: https://doi.org/10.7910/DVN/D79LV8

Citation Formats


                    Austin, M. E., Marinoni, A., Walker, M. L., Brookman, M. W., deGrassie, J. S., Hyatt, A. W., McKee, G. R., Petty, C. C., Rhodes, T. L., Smith, S. P., Sung, C., Thome, K. E., and Turnbull, A. D. Achievement of Reactor-Relevant Performance in Negative Triangularity Shape in the DIII-D Tokamak.  United States: N. p., 2021. 
        Web.  doi:10.7910/DVN/D79LV8.

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                    Austin, M. E., Marinoni, A., Walker, M. L., Brookman, M. W., deGrassie, J. S., Hyatt, A. W., McKee, G. R., Petty, C. C., Rhodes, T. L., Smith, S. P., Sung, C., Thome, K. E., & Turnbull, A. D. Achievement of Reactor-Relevant Performance in Negative Triangularity Shape in the DIII-D Tokamak.  United States.  doi:https://doi.org/10.7910/DVN/D79LV8

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                    Austin, M. E., Marinoni, A., Walker, M. L., Brookman, M. W., deGrassie, J. S., Hyatt, A. W., McKee, G. R., Petty, C. C., Rhodes, T. L., Smith, S. P., Sung, C., Thome, K. E., and Turnbull, A. D. 2021.  
"Achievement of Reactor-Relevant Performance in Negative Triangularity Shape in the DIII-D Tokamak".  United States.  doi:https://doi.org/10.7910/DVN/D79LV8.  https://www.osti.gov/servlets/purl/1882406. Pub date:Wed May 05 00:00:00 EDT 2021

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@article{osti_1882406,

  title        = {Achievement of Reactor-Relevant Performance in Negative Triangularity Shape in the DIII-D Tokamak},

  author       = {Austin, M. E. and Marinoni, A. and Walker, M. L. and Brookman, M. W. and deGrassie, J. S. and Hyatt, A. W. and McKee, G. R. and Petty, C. C. and Rhodes, T. L. and Smith, S. P. and Sung, C. and Thome, K. E. and Turnbull, A. D.},

  abstractNote = {Plasma discharges with a negative triangularity (δ=−0.4) shape have been created in the DIII-D tokamak with a significant normalized beta (βN=2.7) and confinement characteristic of the high confinement mode (H98y2=1.2) despite the absence of an edge pressure pedestal and no edge localized modes (ELMs). These inner-wall-limited plasmas have a similar global performance as a positive triangularity (δ=+0.4) ELMing H-mode discharge with the same plasma current, elongation and cross sectional area. For cases both of dominant electron cyclotron heating with Te/Ti>1 and dominant neutral beam injection heating with Te/Ti=1, turbulent fluctuations over radii 0.5<ρ<0.9 were reduced by 10–50% in the negative triangularity shape compared to the matching positive triangularity shape, depending on the radius and conditions.},

  doi          = {10.7910/DVN/D79LV8},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Wed May 05 00:00:00 EDT 2021},

  month        = {Wed May 05 00:00:00 EDT 2021}

}

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DOI: https://doi.org/10.7910/DVN/D79LV8

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