Power transfer and current generation of fast ions with large-ko waves in Tokamak plasmas

Jukka Heikkinen, Kari Sipilä

Research output: Contribution to journalArticleScientificpeer-review

71 Citations (Scopus)

Abstract

The direction and magnitude of power and momentum exchange between fast ions and electrostatic waves in slab and toroidal systems are obtained from global Monte Carlo simulations that include the quasilinear wave‐induced ion diffusion both in velocity space and through a radially localized (lower hybrid) wave structure with propagation in one preferential poloidal direction in tokamaks.
The model considers a full linearized collision model, finite fast ion orbits, and losses in toroidal geometry, and can properly treat the boundary effects on the particle–wave interaction in the configuration space. For an isotropic steady ion source, reduction of wave Landau damping but no wave amplification by wave localization is found for a Gaussian wave intensity distribution in radius, irrespective of the steepness of the radial gradient of the fast ion source rate. Enhanced wave‐driven fast ion current, with magnitude, direction, and profile determined by the boundary conditions, net power transfer, and fast ion radial transport, is found to follow from the asymmetry in the parallel wave number spectrum created by the finite poloidal magnetic field.
In the presence of intense well‐penetrated waves the current carried by fusion α particles can be controlled by the choice of the poloidal wave number spectrum and the total current can greatly exceed the neoclassical bootstrap current of the α particles in a reactor.
Original languageEnglish
Pages (from-to)3724-3733
JournalPhysics of Plasmas
Volume2
Issue number10
DOIs
Publication statusPublished - 1995
MoE publication typeA1 Journal article-refereed

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ions
ion sources
wave amplification
electrostatic waves
Landau damping
ion currents
slabs
fusion
reactors
asymmetry
boundary conditions
slopes
orbits
momentum
gradients
collisions
radii
propagation
profiles
geometry

Cite this

Heikkinen, Jukka ; Sipilä, Kari. / Power transfer and current generation of fast ions with large-ko waves in Tokamak plasmas. In: Physics of Plasmas. 1995 ; Vol. 2, No. 10. pp. 3724-3733.
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title = "Power transfer and current generation of fast ions with large-ko waves in Tokamak plasmas",
abstract = "The direction and magnitude of power and momentum exchange between fast ions and electrostatic waves in slab and toroidal systems are obtained from global Monte Carlo simulations that include the quasilinear wave‐induced ion diffusion both in velocity space and through a radially localized (lower hybrid) wave structure with propagation in one preferential poloidal direction in tokamaks. The model considers a full linearized collision model, finite fast ion orbits, and losses in toroidal geometry, and can properly treat the boundary effects on the particle–wave interaction in the configuration space. For an isotropic steady ion source, reduction of wave Landau damping but no wave amplification by wave localization is found for a Gaussian wave intensity distribution in radius, irrespective of the steepness of the radial gradient of the fast ion source rate. Enhanced wave‐driven fast ion current, with magnitude, direction, and profile determined by the boundary conditions, net power transfer, and fast ion radial transport, is found to follow from the asymmetry in the parallel wave number spectrum created by the finite poloidal magnetic field. In the presence of intense well‐penetrated waves the current carried by fusion α particles can be controlled by the choice of the poloidal wave number spectrum and the total current can greatly exceed the neoclassical bootstrap current of the α particles in a reactor.",
author = "Jukka Heikkinen and Kari Sipil{\"a}",
note = "Project code: ENE0630",
year = "1995",
doi = "10.1063/1.871072",
language = "English",
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pages = "3724--3733",
journal = "Physics of Plasmas",
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Power transfer and current generation of fast ions with large-ko waves in Tokamak plasmas. / Heikkinen, Jukka; Sipilä, Kari.

In: Physics of Plasmas, Vol. 2, No. 10, 1995, p. 3724-3733.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Power transfer and current generation of fast ions with large-ko waves in Tokamak plasmas

AU - Heikkinen, Jukka

AU - Sipilä, Kari

N1 - Project code: ENE0630

PY - 1995

Y1 - 1995

N2 - The direction and magnitude of power and momentum exchange between fast ions and electrostatic waves in slab and toroidal systems are obtained from global Monte Carlo simulations that include the quasilinear wave‐induced ion diffusion both in velocity space and through a radially localized (lower hybrid) wave structure with propagation in one preferential poloidal direction in tokamaks. The model considers a full linearized collision model, finite fast ion orbits, and losses in toroidal geometry, and can properly treat the boundary effects on the particle–wave interaction in the configuration space. For an isotropic steady ion source, reduction of wave Landau damping but no wave amplification by wave localization is found for a Gaussian wave intensity distribution in radius, irrespective of the steepness of the radial gradient of the fast ion source rate. Enhanced wave‐driven fast ion current, with magnitude, direction, and profile determined by the boundary conditions, net power transfer, and fast ion radial transport, is found to follow from the asymmetry in the parallel wave number spectrum created by the finite poloidal magnetic field. In the presence of intense well‐penetrated waves the current carried by fusion α particles can be controlled by the choice of the poloidal wave number spectrum and the total current can greatly exceed the neoclassical bootstrap current of the α particles in a reactor.

AB - The direction and magnitude of power and momentum exchange between fast ions and electrostatic waves in slab and toroidal systems are obtained from global Monte Carlo simulations that include the quasilinear wave‐induced ion diffusion both in velocity space and through a radially localized (lower hybrid) wave structure with propagation in one preferential poloidal direction in tokamaks. The model considers a full linearized collision model, finite fast ion orbits, and losses in toroidal geometry, and can properly treat the boundary effects on the particle–wave interaction in the configuration space. For an isotropic steady ion source, reduction of wave Landau damping but no wave amplification by wave localization is found for a Gaussian wave intensity distribution in radius, irrespective of the steepness of the radial gradient of the fast ion source rate. Enhanced wave‐driven fast ion current, with magnitude, direction, and profile determined by the boundary conditions, net power transfer, and fast ion radial transport, is found to follow from the asymmetry in the parallel wave number spectrum created by the finite poloidal magnetic field. In the presence of intense well‐penetrated waves the current carried by fusion α particles can be controlled by the choice of the poloidal wave number spectrum and the total current can greatly exceed the neoclassical bootstrap current of the α particles in a reactor.

U2 - 10.1063/1.871072

DO - 10.1063/1.871072

M3 - Article

VL - 2

SP - 3724

EP - 3733

JO - Physics of Plasmas

JF - Physics of Plasmas

SN - 1527-2419

IS - 10

ER -