RF beam scattering by cylindrical filaments and interfacial density fluctuations

Valvis, S. I.; Zisis, A.; Papadopoulos, A.; Papagiannis, P.; Ram, A. K.; Hizanidis, K.; Tigelis, I. G.; Glytsis, E.

doi:10.7910/DVN/HNSWSE

Title: RF beam scattering by cylindrical filaments and interfacial density fluctuations

Dataset
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Abstract

Radio Frequency (RF) waves are routinely used in tokamaks for heating, current drive, NTM control, as well as for diagnostics purposes. Frequently, RF waves, aiming towards the plasma core, propagate through a turbulent environment. The latter can exhibit strong coherent density fluctuations as well as filamentary structures mainly (though, not perfectly) aligned along the local magnetic field lines. The scattering process of RF waves by these structures is studied both analytically and numerically. RF waves can be either single plane waves or spatially confined beams. For that purpose, the filaments are considered to have cylindrical shape with infinite length with the cylinder axis not aligned with the local magnetic field and the results are compared to the ones from the study of the aligned case. On the other hand, the interfacial density fluctuations are considered periodic with spatial periods larger, smaller or of the same order of the wavelength of the incident RF waves. The frequency range of the RF waves studied is mainly in the Electron Cyclotron (EC) range of frequencies for ITER-like and Medium Size Tokamak applications. Furthermore, the study covers a variety of density contrasts, filament sizes and fluctuation strengths.

Authors:

Valvis, S. I.; Zisis, A.; Papadopoulos, A.; Papagiannis, P.; Ram, A. K.; Hizanidis, K.; Tigelis, I. G.; Glytsis, E.

OSTI

Publication Date:: Wed Jun 26 04:00:00 UTC 2019

DOE Contract Number:: FC02-01ER54648; FG02-91ER54109; FG02-99ER54525

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:: 1881427

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

Citation Formats


                    Valvis, S. I., Zisis, A., Papadopoulos, A., Papagiannis, P., Ram, A. K., Hizanidis, K., Tigelis, I. G., and Glytsis, E. RF beam scattering by cylindrical filaments and interfacial density fluctuations.  United States: N. p., 2019. 
        Web.  doi:10.7910/DVN/HNSWSE.

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                    Valvis, S. I., Zisis, A., Papadopoulos, A., Papagiannis, P., Ram, A. K., Hizanidis, K., Tigelis, I. G., & Glytsis, E. RF beam scattering by cylindrical filaments and interfacial density fluctuations.  United States.  doi:https://doi.org/10.7910/DVN/HNSWSE

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                    Valvis, S. I., Zisis, A., Papadopoulos, A., Papagiannis, P., Ram, A. K., Hizanidis, K., Tigelis, I. G., and Glytsis, E. 2019.  
"RF beam scattering by cylindrical filaments and interfacial density fluctuations".  United States.  doi:https://doi.org/10.7910/DVN/HNSWSE.  https://www.osti.gov/servlets/purl/1881427. Pub date:Wed Jun 26 04:00:00 UTC 2019

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@article{osti_1881427,

  title        = {RF beam scattering by cylindrical filaments and interfacial density fluctuations},

  author       = {Valvis, S. I. and Zisis, A. and Papadopoulos, A. and Papagiannis, P. and Ram, A. K. and Hizanidis, K. and Tigelis, I. G. and Glytsis, E.},

  abstractNote = {Radio Frequency (RF) waves are routinely used in tokamaks for heating, current drive, NTM control, as well as for diagnostics purposes. Frequently, RF waves, aiming towards the plasma core, propagate through a turbulent environment. The latter can exhibit strong coherent density fluctuations as well as filamentary structures mainly (though, not perfectly) aligned along the local magnetic field lines. The scattering process of RF waves by these structures is studied both analytically and numerically. RF waves can be either single plane waves or spatially confined beams. For that purpose, the filaments are considered to have cylindrical shape with infinite length with the cylinder axis not aligned with the local magnetic field and the results are compared to the ones from the study of the aligned case. On the other hand, the interfacial density fluctuations are considered periodic with spatial periods larger, smaller or of the same order of the wavelength of the incident RF waves. The frequency range of the RF waves studied is mainly in the Electron Cyclotron (EC) range of frequencies for ITER-like and Medium Size Tokamak applications. Furthermore, the study covers a variety of density contrasts, filament sizes and fluctuation strengths.},

  doi          = {10.7910/DVN/HNSWSE},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Wed Jun 26 04:00:00 UTC 2019},

  month        = {Wed Jun 26 04:00:00 UTC 2019}

}

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

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