Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas
Abstract
In this study, a reduced model of quasilinear velocity diffusion by a small Larmor radius approximation is derived to couple the Maxwell’s equations and the Fokker Planck equation selfconsistently for the ion cyclotron range of frequency waves in a tokamak. The reduced model ensures the important properties of the full model by KennelEngelmann diffusion, such as diffusion directions, wave polarizations, and Htheorem. The kinetic energy change (Wdot ) is used to derive the reduced model diffusion coefficients for the fundamental damping (n = 1) and the second harmonic damping (n = 2) to the lowest order of the finite Larmor radius expansion. The quasilinear diffusion coefficients are implemented in a coupled code (TORICCQL3D) with the equivalent reduced model of the dielectric tensor. We also present the simulations of the ITER minority heating scenario, in which the reduced model is verified within the allowable errors from the full model results.
 Authors:
 Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 XCEL Engineering, Oak Ridge, TN (United States)
 CompX, Del Mar, CA (United States)
 Publication Date:
 Research Org.:
 Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC24)
 OSTI Identifier:
 1353216
 Alternate Identifier(s):
 OSTI ID: 1361850
 Grant/Contract Number:
 FC0201ER54648; AC0205CH11231; AC02CH0911466
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physics of Plasmas
 Additional Journal Information:
 Journal Volume: 24; Journal Issue: 5; Journal ID: ISSN 1070664X
 Publisher:
 American Institute of Physics (AIP)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; RF heating; tokamak; kinetic theory; cyclotron damping
Citation Formats
Lee, Jungpyo, Wright, John, Bertelli, Nicola, Jaeger, Erwin F., Valeo, Ernest, Harvey, Robert, and Bonoli, Paul. Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas. United States: N. p., 2017.
Web. doi:10.1063/1.4982060.
Lee, Jungpyo, Wright, John, Bertelli, Nicola, Jaeger, Erwin F., Valeo, Ernest, Harvey, Robert, & Bonoli, Paul. Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas. United States. doi:10.1063/1.4982060.
Lee, Jungpyo, Wright, John, Bertelli, Nicola, Jaeger, Erwin F., Valeo, Ernest, Harvey, Robert, and Bonoli, Paul. Mon .
"Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas". United States.
doi:10.1063/1.4982060. https://www.osti.gov/servlets/purl/1353216.
@article{osti_1353216,
title = {Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas},
author = {Lee, Jungpyo and Wright, John and Bertelli, Nicola and Jaeger, Erwin F. and Valeo, Ernest and Harvey, Robert and Bonoli, Paul},
abstractNote = {In this study, a reduced model of quasilinear velocity diffusion by a small Larmor radius approximation is derived to couple the Maxwell’s equations and the Fokker Planck equation selfconsistently for the ion cyclotron range of frequency waves in a tokamak. The reduced model ensures the important properties of the full model by KennelEngelmann diffusion, such as diffusion directions, wave polarizations, and Htheorem. The kinetic energy change (Wdot ) is used to derive the reduced model diffusion coefficients for the fundamental damping (n = 1) and the second harmonic damping (n = 2) to the lowest order of the finite Larmor radius expansion. The quasilinear diffusion coefficients are implemented in a coupled code (TORICCQL3D) with the equivalent reduced model of the dielectric tensor. We also present the simulations of the ITER minority heating scenario, in which the reduced model is verified within the allowable errors from the full model results.},
doi = {10.1063/1.4982060},
journal = {Physics of Plasmas},
number = 5,
volume = 24,
place = {United States},
year = {Mon Apr 24 00:00:00 EDT 2017},
month = {Mon Apr 24 00:00:00 EDT 2017}
}

Efficient ion heating via finiteLarmorradius ioncyclotron waves in a plasma
Ion heating by externally launched ion Bernstein waves is investigated in the ACT1 hydrogen plasma. Detailed measurements of wave absorption and of the ion temperature profiles have clearly identified various heating layers near the ioncyclotron harmonics of deuterium like and tritium like ions. The observed bulk ion heating with heating quality factor of 10 eV/W x(10/sup 10/) cm/sup 3/ and the power balance estimates suggest excellent overall efficiency for finiteLarmorradiusioncyclotron resonancefrequency heating. 
Comments on finite Larmor radius models for ion cyclotron range of frequencies heating in tokamaks
The accuracy of standard finite Larmor radius (FLR) models for wave propagation in the ion cyclotron range of frequencies (ICRF) is compared against full hot plasma models. For multiple ion species plasmas, the FLR model is shown to predict the presence of a spurious second harmonic ionion type resonance between the second harmonic cyclotron layers of two ion species. It is shown explicitly here that the spurious resonance is an artifact of the FLR models and that no absorption occurs in the plasma as a result of this resonance.''