High Field Side Launch of RF Waves: A New Approach to Reactor Actuators

Wallace, G. M.; Baek, S. G.; Bonoli, P. T.; Faust, I. C.; LaBombard, B. L.; Lin, Y.; Mumgaard, R. T.; Parker, R. R.; Shiraiwa, S.; Vieira, R.; Whyte, D. G.; Wukitch, S. J.

doi:10.7910/DVN/GH2CS8

Title: High Field Side Launch of RF Waves: A New Approach to Reactor Actuators

Dataset
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Abstract

Launching radio frequency (RF) waves from the high field side (HFS) of a tokamak offers significant advantages over low field side (LFS) launch with respect to both wave physics and plasma material interactions (PMI). For lower hybrid (LH) waves, the higher magnetic field opens the window between wave accessibility and the condition for strong electron Landau damping, allowing LH waves from the HFS to penetrate into the core of a burning plasma, while waves launched from the LFS are restricted to the periphery of the plasma. The lower of waves absorbed at higher yields a higher current drive efficiency as well. In the ion cyclotron range of frequencies (ICRF), HFS launch allows for direct access to the mode conversion layer where mode converted waves absorb strongly on thermal electrons and ions, thus avoiding the generation of energetic minority ion tails. The absence of turbulent heat and particle fluxes on the HFS, particularly in double null configuration, makes it the ideal location to minimize PMI damage to the antenna structure. The quiescent SOL also eliminates the need to couple LH waves across a long distance to the separatrix, as the antenna can be located close to plasma without risking damage tomore »« less

Authors:

Wallace, G. M.; Baek, S. G.; Bonoli, P. T.; Faust, I. C.; LaBombard, B. L.; Lin, Y.; Mumgaard, R. T.; Parker, R. R.; Shiraiwa, S.; Vieira, R.; Whyte, D. G.; Wukitch, S. J.

OSTI

Publication Date:: Mon Mar 01 23:00:00 EST 2021

DOE Contract Number:: FC02-99ER54512

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:: 1881834

DOI:: https://doi.org/10.7910/DVN/GH2CS8

Citation Formats


                    Wallace, G. M., Baek, S. G., Bonoli, P. T., Faust, I. C., LaBombard, B. L., Lin, Y., Mumgaard, R. T., Parker, R. R., Shiraiwa, S., Vieira, R., Whyte, D. G., and Wukitch, S. J. High Field Side Launch of RF Waves: A New Approach to Reactor Actuators.  United States: N. p., 2021. 
        Web.  doi:10.7910/DVN/GH2CS8.

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                    Wallace, G. M., Baek, S. G., Bonoli, P. T., Faust, I. C., LaBombard, B. L., Lin, Y., Mumgaard, R. T., Parker, R. R., Shiraiwa, S., Vieira, R., Whyte, D. G., & Wukitch, S. J. High Field Side Launch of RF Waves: A New Approach to Reactor Actuators.  United States.  doi:https://doi.org/10.7910/DVN/GH2CS8

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                    Wallace, G. M., Baek, S. G., Bonoli, P. T., Faust, I. C., LaBombard, B. L., Lin, Y., Mumgaard, R. T., Parker, R. R., Shiraiwa, S., Vieira, R., Whyte, D. G., and Wukitch, S. J. 2021.  
"High Field Side Launch of RF Waves: A New Approach to Reactor Actuators".  United States.  doi:https://doi.org/10.7910/DVN/GH2CS8.  https://www.osti.gov/servlets/purl/1881834. Pub date:Mon Mar 01 23:00:00 EST 2021

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@article{osti_1881834,

  title        = {High Field Side Launch of RF Waves: A New Approach to Reactor Actuators},

  author       = {Wallace, G. M. and Baek, S. G. and Bonoli, P. T. and Faust, I. C. and LaBombard, B. L. and Lin, Y. and Mumgaard, R. T. and Parker, R. R. and Shiraiwa, S. and Vieira, R. and Whyte, D. G. and Wukitch, S. J.},

  abstractNote = {Launching radio frequency (RF) waves from the high field side (HFS) of a tokamak offers significant advantages over low field side (LFS) launch with respect to both wave physics and plasma material interactions (PMI). For lower hybrid (LH) waves, the higher magnetic field opens the window between wave accessibility and the condition for strong electron Landau damping, allowing LH waves from the HFS to penetrate into the core of a burning plasma, while waves launched from the LFS are restricted to the periphery of the plasma. The lower of waves absorbed at higher yields a higher current drive efficiency as well. In the ion cyclotron range of frequencies (ICRF), HFS launch allows for direct access to the mode conversion layer where mode converted waves absorb strongly on thermal electrons and ions, thus avoiding the generation of energetic minority ion tails. The absence of turbulent heat and particle fluxes on the HFS, particularly in double null configuration, makes it the ideal location to minimize PMI damage to the antenna structure. The quiescent SOL also eliminates the need to couple LH waves across a long distance to the separatrix, as the antenna can be located close to plasma without risking damage to the structure. Improved impurity screening on the HFS will help eliminate the long-standing issues of high Z impurity accumulation with ICRF.},

  doi          = {10.7910/DVN/GH2CS8},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Mon Mar 01 23:00:00 EST 2021},

  month        = {Mon Mar 01 23:00:00 EST 2021}

}

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DOI: https://doi.org/10.7910/DVN/GH2CS8

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