Consequences of toroidal effects in lower hybrid heating of tokamaks

doi:10.2172/5259438

Title: Consequences of toroidal effects in lower hybrid heating of tokamaks

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Abstract

The lower hybrid slow wave tends to follow magnetic field lines. Therefore, a generalization of Snell's Law modifies the wave length along the magnetic field as the wave moves inward from an exciter through regions of varying magnetic field strength. Predicting the consequences requires a numerical treatment, which has been developed in recent years by several authors. This paper searches for some general statements on the problem by analyzing many particular cases, without allowing for scattering, multiple traverses of the plasma radius, and non-linear effects. We find that the range of parameter suitable for ion heating varies from that predicted by simple estimates, and is dependent on launch position; and that electron heating including current drive is best pursued with unidirectional launching from a coupler at the top (or bottom) of the torus if the wave frequency is close to linear mode conversion condition.

Authors:: Bernabei, S.; Ignat, D.W.

Publication Date:: Tue Jan 19 00:00:00 EST 1982

Research Org.:: Princeton Univ., NJ (USA). Plasma Physics Lab.

OSTI Identifier:: 5259438

Report Number(s):: PPPL-1870
ON: DE82007675; TRN: 82-014453

DOE Contract Number:: AC02-76CH03073

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; HIGH-FREQUENCY HEATING; HYBRID RESONANCE; TOKAMAK DEVICES; COUPLING; ION TEMPERATURE; NONLINEAR PROBLEMS; TOROIDAL CONFIGURATION; ANNULAR SPACE; CLOSED PLASMA DEVICES; CONFIGURATION; HEATING; PLASMA HEATING; RESONANCE; SPACE; THERMONUCLEAR DEVICES; 700101* - Fusion Energy- Plasma Research- Confinement, Heating, & Production

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                    Bernabei, S., and Ignat, D.W. Consequences of toroidal effects in lower hybrid heating of tokamaks.  United States: N. p., 1982. 
        Web.  doi:10.2172/5259438.

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                    Bernabei, S., & Ignat, D.W. Consequences of toroidal effects in lower hybrid heating of tokamaks.  United States.  doi:10.2172/5259438.

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                    Bernabei, S., and Ignat, D.W. Tue .  
        "Consequences of toroidal effects in lower hybrid heating of tokamaks".  United States.  
        doi:10.2172/5259438.  https://www.osti.gov/servlets/purl/5259438.

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@article{osti_5259438,

  title        = {Consequences of toroidal effects in lower hybrid heating of tokamaks},

  author       = {Bernabei, S. and Ignat, D.W.},

  abstractNote = {The lower hybrid slow wave tends to follow magnetic field lines. Therefore, a generalization of Snell's Law modifies the wave length along the magnetic field as the wave moves inward from an exciter through regions of varying magnetic field strength. Predicting the consequences requires a numerical treatment, which has been developed in recent years by several authors. This paper searches for some general statements on the problem by analyzing many particular cases, without allowing for scattering, multiple traverses of the plasma radius, and non-linear effects. We find that the range of parameter suitable for ion heating varies from that predicted by simple estimates, and is dependent on launch position; and that electron heating including current drive is best pursued with unidirectional launching from a coupler at the top (or bottom) of the torus if the wave frequency is close to linear mode conversion condition.},

  doi          = {10.2172/5259438},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Jan 19 00:00:00 EST 1982},

  month        = {Tue Jan 19 00:00:00 EST 1982}

}

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