Scattering of radiofrequency waves by randomly modulated density interfaces in the edge of fusion plasmas

Papadopoulos, A. D.; Glytsis, E. N.; Ram, A. K.; Hizanidis, K.

doi:10.1017/s0022377821000647

Scattering of radiofrequency waves by randomly modulated density interfaces in the edge of fusion plasmas

Journal Article · Fri Jul 09 00:00:00 EDT 2021 · Journal of Plasma Physics

DOI:https://doi.org/10.1017/s0022377821000647· OSTI ID:1848997

^[1]; Glytsis, E. N. ^[2]; Ram, A. K. ^[3]; Hizanidis, K. ^[2]

National Technical University of Athens (Greece); OSTI
National Technical University of Athens (Greece)
Massachusetts Institute of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center

In the scrape-off layer and the edge region of a tokamak, the plasma is strongly turbulent and scatters the radiofrequency (RF) electromagnetic waves that propagate through this region. It is important to know the spectral properties of these scattered RF waves, whether used for diagnostics or for heating and current drive. The spectral changes influence the interpretation of the obtained diagnostic data, and the current and heating profiles. A full-wave, three-dimensional (3-D) electromagnetic code ScaRF has been developed for studying the RF wave propagation through turbulent plasma. ScaRF is a finite-difference frequency-domain (FDFD) method used for solving Maxwell's equations. The magnetized plasma is defined through the cold plasma by the anisotropic permittivity tensor. As a result, ScaRF can be used to study the scattering of any cold plasma RF wave. It can also be used for the study of the scattering of electron cyclotron waves in ITER-type and medium-sized tokamaks such as TCV, ASDEX-U and DIII-D. For the case of medium-sized tokamaks, there is experimental evidence that drift waves and rippling modes are present in the edge region. Hence, we have studied the scattering of RF waves by periodic density interfaces (plasma gratings) in the form of a superposition of spatial modes with varying periodicity and random amplitudes. The power reflection coefficient (a random variable) is calculated for different realizations of the density interface. In this work, the uncertainty of the power reflection coefficient is rigorously quantified by use of the Polynomial Chaos Expansion method in conjunction with the Smolyak sparse-grid integration, which is known as the PCE-SG method. The PCE-SG method is proven to be accurate and more efficient compared with alternative methods such as the Monte Carlo (MC) approach.

View Accepted Manuscript (DOE)

Research Organization:: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center

Sponsoring Organization:: USDOE Office of Science (SC), Fusion Energy Sciences (FES); EUROfusion Consortium

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

OSTI ID:: 1848997

Journal Information:: Journal of Plasma Physics, Journal Name: Journal of Plasma Physics Journal Issue: 4 Vol. 87; ISSN 0022-3778

Publisher:: Cambridge University PressCopyright Statement

Country of Publication:: United States

Language:: English

References (20)

Finite-Difference Time-Domain Analysis Taflove, Allen; Hagness, Susan C. Encyclopedia of RF and Microwave Engineering https://doi.org/10.1002/0471654507.eme123	book	April 2005
Smolyak cubature of given polynomial degree with few nodes for increasing dimension Petras, Knut Numerische Mathematik, Vol. 93, Issue 4 https://doi.org/10.1007/s002110200401	journal	February 2003
Adaptive sparse polynomial chaos expansion based on least angle regression Blatman, Géraud; Sudret, Bruno Journal of Computational Physics, Vol. 230, Issue 6 https://doi.org/10.1016/j.jcp.2010.12.021	journal	March 2011
Distinguishing correct from incorrect PML proposals and a corrected unsplit PML for anisotropic, dispersive media Oskooi, Ardavan; Johnson, Steven G. Journal of Computational Physics, Vol. 230, Issue 7 https://doi.org/10.1016/j.jcp.2011.01.006	journal	April 2011
Polynomial chaos expansion for sensitivity analysis Crestaux, Thierry; Le Maıˆtre, Olivier; Martinez, Jean-Marc Reliability Engineering & System Safety, Vol. 94, Issue 7 https://doi.org/10.1016/j.ress.2008.10.008	journal	July 2009
Diffraction of radio frequency waves by spatially modulated interfaces in the plasma edge in tokamaks Papadopoulos, A. D.; Glytsis, E. N.; Ram, A. K. Journal of Plasma Physics, Vol. 85, Issue 3 https://doi.org/10.1017/S0022377819000308	journal	June 2019
Radially propagating fluctuation structures in the scrape-off layer of Alcator C-Mod Grulke, O.; Terry, J. L.; LaBombard, B. Physics of Plasmas, Vol. 13, Issue 1 https://doi.org/10.1063/1.2164991	journal	January 2006
Blob birth and transport in the tokamak edge plasma: Analysis of imaging data Myra, J. R.; D’Ippolito, D. A.; Stotler, D. P. Physics of Plasmas, Vol. 13, Issue 9 https://doi.org/10.1063/1.2355668	journal	September 2006
Collisionality and magnetic geometry effects on tokamak edge turbulent transport. I. A two-region model with application to blobs Myra, J. R.; Russell, D. A.; D’Ippolito, D. A. Physics of Plasmas, Vol. 13, Issue 11 https://doi.org/10.1063/1.2364858	journal	November 2006
Time-dependent 2-D modeling of edge plasma transport with high intermittency due to blobs Pigarov, A. Yu.; Krasheninnikov, S. I.; Rognlien, T. D. Physics of Plasmas, Vol. 19, Issue 7 https://doi.org/10.1063/1.4739464	journal	July 2012
Scattering of radio frequency waves by blobs in tokamak plasmas Ram, Abhay K.; Hizanidis, Kyriakos; Kominis, Yannis Physics of Plasmas, Vol. 20, Issue 5 https://doi.org/10.1063/1.4803898	journal	May 2013
Scattering of radio frequency waves by cylindrical density filaments in tokamak plasmas Ram, Abhay K.; Hizanidis, Kyriakos Physics of Plasmas, Vol. 23, Issue 2 https://doi.org/10.1063/1.4941588	journal	February 2016
Computational studies on scattering of radio frequency waves by density filaments in fusion plasmas Ioannidis, Zisis C.; Ram, Abhay K.; Hizanidis, Kyriakos Physics of Plasmas, Vol. 24, Issue 10 https://doi.org/10.1063/1.4992032	journal	October 2017
Turbulent structure in the edge plasma of the TEXT tokamak Ritz, Ch. P.; Bengtson, Roger D.; Levinson, S. J. Physics of Fluids, Vol. 27, Issue 12 https://doi.org/10.1063/1.864611	journal	January 1984
Edge turbulence measurements in toroidal fusion devices Zweben, S. J.; Boedo, J. A.; Grulke, O. Plasma Physics and Controlled Fusion, Vol. 49, Issue 7 https://doi.org/10.1088/0741-3335/49/7/S01	journal	June 2007
Propagation in 3D of microwaves through density perturbations Williams, T. R. N.; Köhn, A.; O'Brien, M. R. Plasma Physics and Controlled Fusion, Vol. 56, Issue 7 https://doi.org/10.1088/0741-3335/56/7/075010	journal	May 2014
Microwave beam broadening due to turbulent plasma density fluctuations within the limit of the Born approximation and beyond Köhn, A.; Guidi, L.; Holzhauer, E. Plasma Physics and Controlled Fusion, Vol. 60, Issue 7 https://doi.org/10.1088/1361-6587/aac000	journal	May 2018
The effect of density fluctuations on electron cyclotron beam broadening and implications for ITER Snicker, A.; Poli, E.; Maj, O. Nuclear Fusion, Vol. 58, Issue 1 https://doi.org/10.1088/1741-4326/aa8d07	journal	November 2017
The Wiener--Askey Polynomial Chaos for Stochastic Differential Equations Xiu, Dongbin; Karniadakis, George Em SIAM Journal on Scientific Computing, Vol. 24, Issue 2 https://doi.org/10.1137/S1064827501387826	journal	January 2002
Performance analysis of waveguide-mode resonant optical filters with stochastic design parameters Papadopoulos, Aristeidis D.; Zygiridis, Theodoros T.; Glytsis, Elias N. Applied Optics, Vol. 57, Issue 12 https://doi.org/10.1364/AO.57.003106	journal	January 2018

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