Theoretical explanation of I-mode impurity removal and energy confinement

Espinosa, Silvia; Catto, Peter J.

doi:10.7910/DVN/1CM1DY

Title: Theoretical explanation of I-mode impurity removal and energy confinement

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Abstract

Improved (I) mode operation maintains the beneficial high energy confinement of high (H) mode while also providing natural fueling to compensate for impurity removal. We show outward collisional radial impurity flux is the robust distinguishing characteristic between I-mode and H-mode, rather than the turbulent weakly coherent mode that is sometimes undetected, perhaps due to its strong spatial localization. In both regimes the E x B flow shear observed may break up eddies to reduce the turbulence level, leading to good bulk energy confinement.

Authors:

Espinosa, Silvia; Catto, Peter J.

OSTI

Publication Date:: Thu Nov 01 00:00:00 EDT 2018

DOE Contract Number:: FG02-91ER54109

Research Org.:: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

OSTI Identifier:: 1880270

DOI:: https://doi.org/10.7910/DVN/1CM1DY

Citation Formats


                    Espinosa, Silvia, and Catto, Peter J. Theoretical explanation of I-mode impurity removal and energy confinement.  United States: N. p., 2018. 
        Web.  doi:10.7910/DVN/1CM1DY.

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                    Espinosa, Silvia, & Catto, Peter J. Theoretical explanation of I-mode impurity removal and energy confinement.  United States.  doi:https://doi.org/10.7910/DVN/1CM1DY

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                    Espinosa, Silvia, and Catto, Peter J. 2018.  
"Theoretical explanation of I-mode impurity removal and energy confinement".  United States.  doi:https://doi.org/10.7910/DVN/1CM1DY.  https://www.osti.gov/servlets/purl/1880270. Pub date:Thu Nov 01 00:00:00 EDT 2018

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@article{osti_1880270,

  title        = {Theoretical explanation of I-mode impurity removal and energy confinement},

  author       = {Espinosa, Silvia and Catto, Peter J.},

  abstractNote = {Improved (I) mode operation maintains the beneficial high energy confinement of high (H) mode while also providing natural fueling to compensate for impurity removal. We show outward collisional radial impurity flux is the robust distinguishing characteristic between I-mode and H-mode, rather than the turbulent weakly coherent mode that is sometimes undetected, perhaps due to its strong spatial localization. In both regimes the E x B flow shear observed may break up eddies to reduce the turbulence level, leading to good bulk energy confinement.},

  doi          = {10.7910/DVN/1CM1DY},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Nov 01 00:00:00 EDT 2018},

  month        = {Thu Nov 01 00:00:00 EDT 2018}

}

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DOI: https://doi.org/10.7910/DVN/1CM1DY

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