Unified modeling of both resonant and non-resonant neoclassical transport under non-axisymmetric magnetic perturbations in tokamaks

Y. Sun, X. Li, K. He, Ker-Chung Shaing

Research output: Contribution to journalArticle

Abstract

A numerical model for neoclassical transport under nonaxisymmetric magnetic perturbations in low collisionality plasmas in tokamaks is developed. To take into account bounce-drift resonances and magnetic drift effects, a Fourier decomposition of the drift kinetic equation in new coordinates, rather than bounce average of it, is employed. A pitch angle scattering collisional operator is used to keep accuracy in the nonresonant regimes or resonant plateau regimes with resonant pitch near pitch space boundaries. Full toroidal geometry effects are also included to increase the accuracy in the modeling of neoclassical transport in the resonant regimes. Neoclassical transport in the most important collisionless regimes, including resonant super-banana plateau and bounce-drift resonances regimes, nonresonant 1/ν and ν - ν regimes, and the transitions between them, can be modeled simultaneously in this model by numerically solving the drift kinetic equation. By application to the neoclassical toroidal viscosity modeling in one discharge in the EAST tokamak, it is found that the bounce-drift resonances dominate the contributions near the plasma core where the plasma E → × B → drift frequency is close to the bounce frequency, while the precessional resonance dominates the contribution near the edge pedestal top where the E → × B → drift frequency is close to zero.

Original languageEnglish
Article number0725041
JournalPhysics of Plasmas
Volume26
Issue number7
DOIs
Publication statusPublished - 2019 Jul 1

Fingerprint

perturbation
kinetic equations
plateaus
pitch (inclination)
viscosity
decomposition
operators
geometry
scattering

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics

Cite this

@article{caefcc3a37dd479e9d93dab26eb6cc8e,
title = "Unified modeling of both resonant and non-resonant neoclassical transport under non-axisymmetric magnetic perturbations in tokamaks",
abstract = "A numerical model for neoclassical transport under nonaxisymmetric magnetic perturbations in low collisionality plasmas in tokamaks is developed. To take into account bounce-drift resonances and magnetic drift effects, a Fourier decomposition of the drift kinetic equation in new coordinates, rather than bounce average of it, is employed. A pitch angle scattering collisional operator is used to keep accuracy in the nonresonant regimes or resonant plateau regimes with resonant pitch near pitch space boundaries. Full toroidal geometry effects are also included to increase the accuracy in the modeling of neoclassical transport in the resonant regimes. Neoclassical transport in the most important collisionless regimes, including resonant super-banana plateau and bounce-drift resonances regimes, nonresonant 1/ν and ν - ν regimes, and the transitions between them, can be modeled simultaneously in this model by numerically solving the drift kinetic equation. By application to the neoclassical toroidal viscosity modeling in one discharge in the EAST tokamak, it is found that the bounce-drift resonances dominate the contributions near the plasma core where the plasma E → × B → drift frequency is close to the bounce frequency, while the precessional resonance dominates the contribution near the edge pedestal top where the E → × B → drift frequency is close to zero.",
author = "Y. Sun and X. Li and K. He and Ker-Chung Shaing",
year = "2019",
month = "7",
day = "1",
doi = "10.1063/1.5099376",
language = "English",
volume = "26",
journal = "Physics of Plasmas",
issn = "1070-664X",
publisher = "American Institute of Physics Publising LLC",
number = "7",

}

Unified modeling of both resonant and non-resonant neoclassical transport under non-axisymmetric magnetic perturbations in tokamaks. / Sun, Y.; Li, X.; He, K.; Shaing, Ker-Chung.

In: Physics of Plasmas, Vol. 26, No. 7, 0725041, 01.07.2019.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Unified modeling of both resonant and non-resonant neoclassical transport under non-axisymmetric magnetic perturbations in tokamaks

AU - Sun, Y.

AU - Li, X.

AU - He, K.

AU - Shaing, Ker-Chung

PY - 2019/7/1

Y1 - 2019/7/1

N2 - A numerical model for neoclassical transport under nonaxisymmetric magnetic perturbations in low collisionality plasmas in tokamaks is developed. To take into account bounce-drift resonances and magnetic drift effects, a Fourier decomposition of the drift kinetic equation in new coordinates, rather than bounce average of it, is employed. A pitch angle scattering collisional operator is used to keep accuracy in the nonresonant regimes or resonant plateau regimes with resonant pitch near pitch space boundaries. Full toroidal geometry effects are also included to increase the accuracy in the modeling of neoclassical transport in the resonant regimes. Neoclassical transport in the most important collisionless regimes, including resonant super-banana plateau and bounce-drift resonances regimes, nonresonant 1/ν and ν - ν regimes, and the transitions between them, can be modeled simultaneously in this model by numerically solving the drift kinetic equation. By application to the neoclassical toroidal viscosity modeling in one discharge in the EAST tokamak, it is found that the bounce-drift resonances dominate the contributions near the plasma core where the plasma E → × B → drift frequency is close to the bounce frequency, while the precessional resonance dominates the contribution near the edge pedestal top where the E → × B → drift frequency is close to zero.

AB - A numerical model for neoclassical transport under nonaxisymmetric magnetic perturbations in low collisionality plasmas in tokamaks is developed. To take into account bounce-drift resonances and magnetic drift effects, a Fourier decomposition of the drift kinetic equation in new coordinates, rather than bounce average of it, is employed. A pitch angle scattering collisional operator is used to keep accuracy in the nonresonant regimes or resonant plateau regimes with resonant pitch near pitch space boundaries. Full toroidal geometry effects are also included to increase the accuracy in the modeling of neoclassical transport in the resonant regimes. Neoclassical transport in the most important collisionless regimes, including resonant super-banana plateau and bounce-drift resonances regimes, nonresonant 1/ν and ν - ν regimes, and the transitions between them, can be modeled simultaneously in this model by numerically solving the drift kinetic equation. By application to the neoclassical toroidal viscosity modeling in one discharge in the EAST tokamak, it is found that the bounce-drift resonances dominate the contributions near the plasma core where the plasma E → × B → drift frequency is close to the bounce frequency, while the precessional resonance dominates the contribution near the edge pedestal top where the E → × B → drift frequency is close to zero.

UR - http://www.scopus.com/inward/record.url?scp=85069754680&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85069754680&partnerID=8YFLogxK

U2 - 10.1063/1.5099376

DO - 10.1063/1.5099376

M3 - Article

AN - SCOPUS:85069754680

VL - 26

JO - Physics of Plasmas

JF - Physics of Plasmas

SN - 1070-664X

IS - 7

M1 - 0725041

ER -