Diffraction of radio frequency waves by spatially modulated interfaces in the plasma edge in tokamaks

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

doi:10.7910/DVN/KRMB3G

Title: Diffraction of radio frequency waves by spatially modulated interfaces in the plasma edge in tokamaks

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Abstract

The use of radio frequency (RF) waves in fusion plasmas for heating, for non-inductive current generation, for profile control, and for diagnostics has been well established. The RF waves, excited by antenna structures placed near the wall of a fusion device, have to propagate through density fluctuations in the plasma edge. These fluctuations can modify the properties of the RF waves that propagate towards the core of the plasma. A full-wave electromagnetic computational code ScaRF based on the finite diifference frequency domain (FDFD) method has been developed to study the effect of density turbulence on RF waves. The anisotropic plasma permittivity used in the scattering studies is that for a magnetized, cold plasma. The code is used to study the propagation of an RF plane wave through a modulated, spatially periodic density interface. Such an interface could arise in the edge region due to magnetohydrodynamic instability or drift waves. The frequency of the plane wave is taken to be in the range of the electron cyclotron frequency. The scattering analysis is applicable to ITER-like plasmas, as well as to plasmas in medium sized tokamaks such as TCV, ASDEX-U, and DIII-D. The effect of diifferent density contrasts across the interface andmore »« less

Authors:

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

OSTI

Publication Date:: Tue Mar 12 04:00:00 UTC 2019

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

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:: 1881292

DOI:: https://doi.org/10.7910/DVN/KRMB3G

Citation Formats


                    Papadopoulos, A. D., Glytsis, E. N., Valvis, S. I., Papagiannis, P., Ram, A. K., Hizanidis, K., and Zisis, A. Diffraction of radio frequency waves by spatially modulated interfaces in the plasma edge in tokamaks.  United States: N. p., 2019. 
        Web.  doi:10.7910/DVN/KRMB3G.

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                    Papadopoulos, A. D., Glytsis, E. N., Valvis, S. I., Papagiannis, P., Ram, A. K., Hizanidis, K., & Zisis, A. Diffraction of radio frequency waves by spatially modulated interfaces in the plasma edge in tokamaks.  United States.  doi:https://doi.org/10.7910/DVN/KRMB3G

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                    Papadopoulos, A. D., Glytsis, E. N., Valvis, S. I., Papagiannis, P., Ram, A. K., Hizanidis, K., and Zisis, A. 2019.  
"Diffraction of radio frequency waves by spatially modulated interfaces in the plasma edge in tokamaks".  United States.  doi:https://doi.org/10.7910/DVN/KRMB3G.  https://www.osti.gov/servlets/purl/1881292. Pub date:Tue Mar 12 04:00:00 UTC 2019

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@article{osti_1881292,

  title        = {Diffraction of radio frequency waves by spatially modulated interfaces in the plasma edge in tokamaks},

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

  abstractNote = {The use of radio frequency (RF) waves in fusion plasmas for heating, for non-inductive current generation, for profile control, and for diagnostics has been well established. The RF waves, excited by antenna structures placed near the wall of a fusion device, have to propagate through density fluctuations in the plasma edge. These fluctuations can modify the properties of the RF waves that propagate towards the core of the plasma. A full-wave electromagnetic computational code ScaRF based on the finite diifference frequency domain (FDFD) method has been developed to study the effect of density turbulence on RF waves. The anisotropic plasma permittivity used in the scattering studies is that for a magnetized, cold plasma. The code is used to study the propagation of an RF plane wave through a modulated, spatially periodic density interface. Such an interface could arise in the edge region due to magnetohydrodynamic instability or drift waves. The frequency of the plane wave is taken to be in the range of the electron cyclotron frequency. The scattering analysis is applicable to ITER-like plasmas, as well as to plasmas in medium sized tokamaks such as TCV, ASDEX-U, and DIII-D. The effect of diifferent density contrasts across the interface and of diifferent spatial modulations are discussed. While ScaRF is used to study a periodic density fluctuation, the code is general enough to include diifferent varieties of density fluctuations in the edge region -- such as blobs and filaments, and spatially random fluctuations.},

  doi          = {10.7910/DVN/KRMB3G},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Mar 12 04:00:00 UTC 2019},

  month        = {Tue Mar 12 04:00:00 UTC 2019}

}

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DOI: https://doi.org/10.7910/DVN/KRMB3G

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