Some effects of MHD activity on impurity transport in the PBX tokamak

Ida, K; Fonck, R J; Hulse, R A; LeBlanc, B

doi:10.2172/6414880

Title: Some effects of MHD activity on impurity transport in the PBX tokamak

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Abstract

The effects of MHD activity on intrinsic impurity transport are studied in ohmic discharges of the Princeton Beta Experiment (PBX) by measuring of the Z/sub eff/ profile from visible bremsstrahlung radiation and the spectral line intensities from ultraviolet spectroscopy. A diffusive/convective transport model, including an internal disruption model, is used to simulate the data. The Z/sub eff/ profile with no MHD activity is fitted with a strong inward convection, characterized by a peaking parameter c/sub v/ (= -a/sup 2/v/2rD) = 11 (3.5, +4.5). At the onset of MHD activity (a large m = 1 n = 1 oscillation followed by sawteeth), this strongly peaked profile is flattened and subsequently reaches a new quasi-equilibrium shape. This profile is characterized by reduced convection (c/sub v/ = 3.6 (-1.1, +1.6), D = 1.4 (-0.7, +5.6) x 10/sup 4/ cm/sup 2//s), in addition to the particle redistribution which accompanies the sawtooth internal disruptions. 10 figs.

Authors:: Ida, K; Fonck, R J; Hulse, R A; LeBlanc, B

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

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

OSTI Identifier:: 6414880

Report Number(s):: PPPL-2264
ON: DE86005037

DOE Contract Number:: AC02-76CH03073

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; IMPURITIES; TRANSPORT; PBX DEVICES; MAGNETOHYDRODYNAMICS; BREMSSTRAHLUNG; COMPUTERIZED SIMULATION; MATHEMATICAL MODELS; CLOSED PLASMA DEVICES; ELECTROMAGNETIC RADIATION; FLUID MECHANICS; HYDRODYNAMICS; MECHANICS; RADIATIONS; SIMULATION; THERMONUCLEAR DEVICES; TOKAMAK DEVICES; 700107* - Fusion Energy- Plasma Research- Instabilities

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                    Ida, K, Fonck, R J, Hulse, R A, and LeBlanc, B. Some effects of MHD activity on impurity transport in the PBX tokamak.  United States: N. p., 1985. 
        Web.  doi:10.2172/6414880.

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                    Ida, K, Fonck, R J, Hulse, R A, & LeBlanc, B. Some effects of MHD activity on impurity transport in the PBX tokamak.  United States.  https://doi.org/10.2172/6414880

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                    Ida, K, Fonck, R J, Hulse, R A, and LeBlanc, B. 1985.  
        "Some effects of MHD activity on impurity transport in the PBX tokamak".  United States.  https://doi.org/10.2172/6414880.  https://www.osti.gov/servlets/purl/6414880.

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@article{osti_6414880,

  title        = {Some effects of MHD activity on impurity transport in the PBX tokamak},

  author       = {Ida, K and Fonck, R J and Hulse, R A and LeBlanc, B},

  abstractNote = {The effects of MHD activity on intrinsic impurity transport are studied in ohmic discharges of the Princeton Beta Experiment (PBX) by measuring of the Z/sub eff/ profile from visible bremsstrahlung radiation and the spectral line intensities from ultraviolet spectroscopy. A diffusive/convective transport model, including an internal disruption model, is used to simulate the data. The Z/sub eff/ profile with no MHD activity is fitted with a strong inward convection, characterized by a peaking parameter c/sub v/ (= -a/sup 2/v/2rD) = 11 (3.5, +4.5). At the onset of MHD activity (a large m = 1 n = 1 oscillation followed by sawteeth), this strongly peaked profile is flattened and subsequently reaches a new quasi-equilibrium shape. This profile is characterized by reduced convection (c/sub v/ = 3.6 (-1.1, +1.6), D = 1.4 (-0.7, +5.6) x 10/sup 4/ cm/sup 2//s), in addition to the particle redistribution which accompanies the sawtooth internal disruptions. 10 figs.},

  doi          = {10.2172/6414880},

  url          = {https://www.osti.gov/biblio/6414880},
  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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