Thermodynamic approach to the interpretation of self-consistent pressure profiles in a tokamak

Dyabilin, K. S.

doi:10.1134/S1063780X15090044

Title: Thermodynamic approach to the interpretation of self-consistent pressure profiles in a tokamak

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Abstract

The phenomenon of invariable pressure profiles in tokamaks is interpreted in the framework of the thermodynamic approach suggesting that invariable self-consistent states correspond to the minimum of free energy. Solutions qualitatively consistent with the experiment are obtained under the assumption that the mechanism for the formation of self-consistent profiles is directly related to equilibrium diamagnetic currents. The dynamics of the system and specific transport phenomena, such as energy and particle pinching and a decrease in the local density under auxiliary electron cyclotron resonance heating (density pump-out), are analyzed in the vicinity of an equilibrium state characterized by a stable pressure profile. The scaling for the energy confinement time deduced from the transport model agrees qualitatively with the ITER scaling based on the analysis of experimental data obtained in many tokamaks. The possibility of using generalized Tsallis statistics to analyze pressure profiles is considered.

Authors:: Dyabilin, K. S.

Publication Date:: Tue Sep 15 00:00:00 EDT 2015

OSTI Identifier:: 22472115

Resource Type:: Journal Article

Journal Name:: Plasma Physics Reports

Additional Journal Information:: Journal Volume: 41; Journal Issue: 9; Other Information: Copyright (c) 2015 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1063-780X

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CONFINEMENT TIME; ECR HEATING; EQUILIBRIUM; FREE ENERGY; ITER TOKAMAK; PLASMA DENSITY; PLASMA PRESSURE; TRANSPORT THEORY

Citation Formats


                    Dyabilin, K. S., and Razumova, K. A., E-mail: Razumova-KA@nrcki.ru. Thermodynamic approach to the interpretation of self-consistent pressure profiles in a tokamak.  United States: N. p., 2015. 
        Web.  doi:10.1134/S1063780X15090044.

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                    Dyabilin, K. S., & Razumova, K. A., E-mail: Razumova-KA@nrcki.ru. Thermodynamic approach to the interpretation of self-consistent pressure profiles in a tokamak.  United States.  https://doi.org/10.1134/S1063780X15090044

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                    Dyabilin, K. S., and Razumova, K. A., E-mail: Razumova-KA@nrcki.ru. 2015.  
        "Thermodynamic approach to the interpretation of self-consistent pressure profiles in a tokamak".  United States.  https://doi.org/10.1134/S1063780X15090044.

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@article{osti_22472115,

  title        = {Thermodynamic approach to the interpretation of self-consistent pressure profiles in a tokamak},

  author       = {Dyabilin, K. S. and Razumova, K. A., E-mail: Razumova-KA@nrcki.ru},

  abstractNote = {The phenomenon of invariable pressure profiles in tokamaks is interpreted in the framework of the thermodynamic approach suggesting that invariable self-consistent states correspond to the minimum of free energy. Solutions qualitatively consistent with the experiment are obtained under the assumption that the mechanism for the formation of self-consistent profiles is directly related to equilibrium diamagnetic currents. The dynamics of the system and specific transport phenomena, such as energy and particle pinching and a decrease in the local density under auxiliary electron cyclotron resonance heating (density pump-out), are analyzed in the vicinity of an equilibrium state characterized by a stable pressure profile. The scaling for the energy confinement time deduced from the transport model agrees qualitatively with the ITER scaling based on the analysis of experimental data obtained in many tokamaks. The possibility of using generalized Tsallis statistics to analyze pressure profiles is considered.},

  doi          = {10.1134/S1063780X15090044},

  url          = {https://www.osti.gov/biblio/22472115},
  journal      = {Plasma Physics Reports},

  issn         = {1063-780X},

  number       = 9,

  volume       = 41,

  place        = {United States},

  year         = {Tue Sep 15 00:00:00 EDT 2015},

  month        = {Tue Sep 15 00:00:00 EDT 2015}

}

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