Nonlinear transfer in heated L-modes approaching the L–H transition threshold in Alcator C-Mod

Cziegler, I.; Tynan, G. R.; Diamond, P. H.; Hubbard, A. E.; Hughes, J. W.; Irby, J.; Terry, J. L.

doi:10.7910/DVN/3RXGCI

Title: Nonlinear transfer in heated L-modes approaching the L–H transition threshold in Alcator C-Mod

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Abstract

Nonlinear transfer processes between large-scale edge flows and the ambient broadband fluctuations have been shown to play a significant role in the dynamics of edge turbulence, including spreading power from coherent modes and suppressing turbulence at the formation of edge transport barriers. In order to predict thresholds of confinement regimes, both the transition dynamics and the parametric dependence of the nonlinear energy transfer must be studied. Since the expected flow damping terms depend on ion collision rates and local safety factors, recent experiments aimed also to explore the nonlinear drive at various values of the plasma current, density and amount of auxiliary heating. Nonlinear interactions between zonal flows and turbulence in L-mode are estimated using bispectral as well as time-resolved methods based on gas-puff-imaging in Alcator C-Mod

Authors:

Cziegler, I.; Tynan, G. R.; Diamond, P. H.; Hubbard, A. E.; Hughes, J. W.; Irby, J.; Terry, J. L.

OSTI

Publication Date:: Thu Jan 10 04:00:00 UTC 2019

DOE Contract Number:: FC02-99ER54512; SC0008689

Research Org.:: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Univ. of California, San Diego, CA (United States)

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

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

OSTI Identifier:: 1880849

DOI:: https://doi.org/10.7910/DVN/3RXGCI

Citation Formats


                    Cziegler, I., Tynan, G. R., Diamond, P. H., Hubbard, A. E., Hughes, J. W., Irby, J., and Terry, J. L. Nonlinear transfer in heated L-modes approaching the L–H transition threshold in Alcator C-Mod.  United States: N. p., 2019. 
        Web.  doi:10.7910/DVN/3RXGCI.

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                    Cziegler, I., Tynan, G. R., Diamond, P. H., Hubbard, A. E., Hughes, J. W., Irby, J., & Terry, J. L. Nonlinear transfer in heated L-modes approaching the L–H transition threshold in Alcator C-Mod.  United States.  doi:https://doi.org/10.7910/DVN/3RXGCI

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                    Cziegler, I., Tynan, G. R., Diamond, P. H., Hubbard, A. E., Hughes, J. W., Irby, J., and Terry, J. L. 2019.  
"Nonlinear transfer in heated L-modes approaching the L–H transition threshold in Alcator C-Mod".  United States.  doi:https://doi.org/10.7910/DVN/3RXGCI.  https://www.osti.gov/servlets/purl/1880849. Pub date:Thu Jan 10 04:00:00 UTC 2019

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@article{osti_1880849,

  title        = {Nonlinear transfer in heated L-modes approaching the L–H transition threshold in Alcator C-Mod},

  author       = {Cziegler, I. and Tynan, G. R. and Diamond, P. H. and Hubbard, A. E. and Hughes, J. W. and Irby, J. and Terry, J. L.},

  abstractNote = {Nonlinear transfer processes between large-scale edge flows and the ambient broadband fluctuations have been shown to play a significant role in the dynamics of edge turbulence, including spreading power from coherent modes and suppressing turbulence at the formation of edge transport barriers. In order to predict thresholds of confinement regimes, both the transition dynamics and the parametric dependence of the nonlinear energy transfer must be studied. Since the expected flow damping terms depend on ion collision rates and local safety factors, recent experiments aimed also to explore the nonlinear drive at various values of the plasma current, density and amount of auxiliary heating. Nonlinear interactions between zonal flows and turbulence in L-mode are estimated using bispectral as well as time-resolved methods based on gas-puff-imaging in Alcator C-Mod},

  doi          = {10.7910/DVN/3RXGCI},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Jan 10 04:00:00 UTC 2019},

  month        = {Thu Jan 10 04:00:00 UTC 2019}

}

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DOI: https://doi.org/10.7910/DVN/3RXGCI

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