U.S. Department of EnergyOffice of Scientific and Technical Information
Homogenization theory for the effective permittivity of a turbulent tokamak plasma in the scrape-off layer
Abstract
There has been a growing interest, over the past few years, on understanding the effect on radio frequency waves due to turbulence in the scrape-off layer of tokamak plasmas. While the far scrape-off layer density width is of the order of centimeters in contemporary tokamaks, in ITER, and in future fusion reactors, the corresponding width will be of the order of tens of centimeters. As such, this could impact the spectral properties of the waves and, consequently, the transport of wave energy and momentum to the core plasma. The turbulence in the scrape-off layer spans a broad range of spatial scales and includes blob and filaments that are elongated along the magnetic field lines. The propagation of radio frequency waves through this tenuous plasma is given by Maxwell's equations. The characteristic properties of the plasma appear as a permittivity tensor in the expression for the current in Ampere's equation. This paper develops a formalism for expressing the permittivity of a turbulent plasma using the homogenization technique. This technique has been extensively used to express the dielectric properties of composite materials that are spatially inhomogeneous, for example, due to the presence of micro-structures. In a similar vein, the turbulent plasma inmore »
- Authors:
-
- OSTI
- Publication Date:
- 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:
- 1881430
- DOI:
- https://doi.org/10.7910/DVN/EDP3BX
Citation Formats
Bairaktaris, F., Hizanidis, K., Ram, A. K., Papagiannis, P., Tsironis, C., Kominis, Y., Glytsis, E., Chellai, O., Alberti, S., and Furno, I. Homogenization theory for the effective permittivity of a turbulent tokamak plasma in the scrape-off layer. United States: N. p., 2019.
Web. doi:10.7910/DVN/EDP3BX.
Bairaktaris, F., Hizanidis, K., Ram, A. K., Papagiannis, P., Tsironis, C., Kominis, Y., Glytsis, E., Chellai, O., Alberti, S., & Furno, I. Homogenization theory for the effective permittivity of a turbulent tokamak plasma in the scrape-off layer. United States. doi:https://doi.org/10.7910/DVN/EDP3BX
Bairaktaris, F., Hizanidis, K., Ram, A. K., Papagiannis, P., Tsironis, C., Kominis, Y., Glytsis, E., Chellai, O., Alberti, S., and Furno, I. 2019.
"Homogenization theory for the effective permittivity of a turbulent tokamak plasma in the scrape-off layer". United States. doi:https://doi.org/10.7910/DVN/EDP3BX. https://www.osti.gov/servlets/purl/1881430. Pub date:Wed Jun 26 04:00:00 UTC 2019
@article{osti_1881430,
title = {Homogenization theory for the effective permittivity of a turbulent tokamak plasma in the scrape-off layer},
author = {Bairaktaris, F. and Hizanidis, K. and Ram, A. K. and Papagiannis, P. and Tsironis, C. and Kominis, Y. and Glytsis, E. and Chellai, O. and Alberti, S. and Furno, I.},
abstractNote = {There has been a growing interest, over the past few years, on understanding the effect on radio frequency waves due to turbulence in the scrape-off layer of tokamak plasmas. While the far scrape-off layer density width is of the order of centimeters in contemporary tokamaks, in ITER, and in future fusion reactors, the corresponding width will be of the order of tens of centimeters. As such, this could impact the spectral properties of the waves and, consequently, the transport of wave energy and momentum to the core plasma. The turbulence in the scrape-off layer spans a broad range of spatial scales and includes blob and filaments that are elongated along the magnetic field lines. The propagation of radio frequency waves through this tenuous plasma is given by Maxwell's equations. The characteristic properties of the plasma appear as a permittivity tensor in the expression for the current in Ampere's equation. This paper develops a formalism for expressing the permittivity of a turbulent plasma using the homogenization technique. This technique has been extensively used to express the dielectric properties of composite materials that are spatially inhomogeneous, for example, due to the presence of micro-structures. In a similar vein, the turbulent plasma in the scrape-off layer is spatially inhomogeneous and can be considered as a composite material in which the micro-structures are filaments and blobs. The classical homogenization technique is not appropriate for the magnetized plasma in the scrape-off layer, as the radio frequency waves span a broad range of wavelengths and frequencies -- from tens of megahertz to hundreds of gigahertz. The formalism in this paper makes use of the Fourier space components of the electric and magnetic fields of the radio frequency waves for the scattered fields and fields inside the filaments and blobs. These are the eigenvectors of the dispersion matrix which, using the Green's function approach, lead to a homogenized dielectric tensor.},
doi = {10.7910/DVN/EDP3BX},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jun 26 04:00:00 UTC 2019},
month = {Wed Jun 26 04:00:00 UTC 2019}
}