Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge

McNeill, D H

doi:10.2172/6358521

Title: Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge

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Abstract

The power balance of the bulk electrons and ions in discharges with 37 kW of applied microwave power in the ELMO Bumpy Torus (EBT) is examined in a zero-dimensional model using data on the intensity and linewidth of the molecular and atomic hydrogen emission. At least 60% of the applied power is ultimately dissipated by processes involving the neutral particles, including dissociation of molecules, ionization of and radiation from atoms, and heating of cold electrons produced during atomic ionization. The molecular influx rate and the density of atoms are used independently to determine the bulk electron particle confinement time, and an upper bound estimate is made of the diffusional power loss from the bulk plasma electrons. Parameters derived from the basic spectroscopic data presented in this paper include the neutral atom density 2 - 5x10/sup 10/ cm/sup -3/, incident molecular flux 3 - 5x10/sup 15/ cm/sup -2/s/sup -1/, bulk ion temperature approx. =3 eV, and particle confinement time <1.1 ms. The bulk electron energy confinement time is 0.7 ms or less in the standard operating regime. Published data on the nonthermal electron and ion populations in the plasma are used to evaluate approximately the overall energy flow in the discharge.more » 54 refs.« less

Authors:: McNeill, D H

Publication Date:: Tue Oct 01 00:00:00 EDT 1985

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

OSTI Identifier:: 6358521

Report Number(s):: PPPL-2248
ON: DE86005044

DOE Contract Number:: AC02-76CH03073

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELMO BUMPY TORUS; ELECTRIC DISCHARGES; ENERGY BALANCE; MICROWAVE HEATING; POWER RANGE 10-100 KW; ELECTRONS; IONS; MATHEMATICAL MODELS; BUMPY TORI; CHARGED PARTICLES; ELEMENTARY PARTICLES; ELMO DEVICES; FERMIONS; HEATING; LEPTONS; MAGNETIC MIRRORS; OPEN PLASMA DEVICES; THERMONUCLEAR DEVICES; 700101* - Fusion Energy- Plasma Research- Confinement, Heating, & Production

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                    McNeill, D H. Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge.  United States: N. p., 1985. 
        Web.  doi:10.2172/6358521.

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                    McNeill, D H. Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge.  United States.  https://doi.org/10.2172/6358521

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                    McNeill, D H. 1985.  
        "Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge".  United States.  https://doi.org/10.2172/6358521.  https://www.osti.gov/servlets/purl/6358521.

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@article{osti_6358521,

  title        = {Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge},

  author       = {McNeill, D H},

  abstractNote = {The power balance of the bulk electrons and ions in discharges with 37 kW of applied microwave power in the ELMO Bumpy Torus (EBT) is examined in a zero-dimensional model using data on the intensity and linewidth of the molecular and atomic hydrogen emission. At least 60% of the applied power is ultimately dissipated by processes involving the neutral particles, including dissociation of molecules, ionization of and radiation from atoms, and heating of cold electrons produced during atomic ionization. The molecular influx rate and the density of atoms are used independently to determine the bulk electron particle confinement time, and an upper bound estimate is made of the diffusional power loss from the bulk plasma electrons. Parameters derived from the basic spectroscopic data presented in this paper include the neutral atom density 2 - 5x10/sup 10/ cm/sup -3/, incident molecular flux 3 - 5x10/sup 15/ cm/sup -2/s/sup -1/, bulk ion temperature approx. =3 eV, and particle confinement time <1.1 ms. The bulk electron energy confinement time is 0.7 ms or less in the standard operating regime. Published data on the nonthermal electron and ion populations in the plasma are used to evaluate approximately the overall energy flow in the discharge. 54 refs.},

  doi          = {10.2172/6358521},

  url          = {https://www.osti.gov/biblio/6358521},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Oct 01 00:00:00 EDT 1985},

  month        = {Tue Oct 01 00:00:00 EDT 1985}

}

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