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Title: Mechanisms governing radial heat fluxes in tokamak plasma

Abstract

A method for analyzing the characteristics of turbulence responsible for radial heat transport is proposed. The method is based on the previously proposed hypotheses (to a great extent, confirmed experimentally) concerning the consistency of normalized pressure profiles in tokamak plasmas and the mechanism of internal transport barrier formation. Using the proposed approach, it is shown that, under an external action on the plasma, when the plasma heat flux onto the wall grows, the spectrum of turbulent modes broadens due to the excitation of modes with lower poloidal numbers m. Thus, in contrast to the conventional diffusion approach, the transport coefficient depends on the flux intensity. A mechanism of formation of internal transport barriers is proposed.

Authors:
; ; ;  [1]
  1. National Research Centre Kurchatov Institute (Russian Federation)
Publication Date:
OSTI Identifier:
22614090
Resource Type:
Journal Article
Resource Relation:
Journal Name: Plasma Physics Reports; Journal Volume: 42; Journal Issue: 9; Other Information: Copyright (c) 2016 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DIFFUSION BARRIERS; EXCITATION; HEAT FLUX; HEAT TRANSFER; HYPOTHESIS; PLASMA; SPECTRA; TOKAMAK DEVICES; TURBULENCE

Citation Formats

Razumova, K. A., E-mail: Razumova-KA@nrcki.ru, Timchenko, N. N., Dnestrovskij, A. Yu., and Lysenko, S. E.. Mechanisms governing radial heat fluxes in tokamak plasma. United States: N. p., 2016. Web. doi:10.1134/S1063780X16090087.
Razumova, K. A., E-mail: Razumova-KA@nrcki.ru, Timchenko, N. N., Dnestrovskij, A. Yu., & Lysenko, S. E.. Mechanisms governing radial heat fluxes in tokamak plasma. United States. doi:10.1134/S1063780X16090087.
Razumova, K. A., E-mail: Razumova-KA@nrcki.ru, Timchenko, N. N., Dnestrovskij, A. Yu., and Lysenko, S. E.. 2016. "Mechanisms governing radial heat fluxes in tokamak plasma". United States. doi:10.1134/S1063780X16090087.
@article{osti_22614090,
title = {Mechanisms governing radial heat fluxes in tokamak plasma},
author = {Razumova, K. A., E-mail: Razumova-KA@nrcki.ru and Timchenko, N. N. and Dnestrovskij, A. Yu. and Lysenko, S. E.},
abstractNote = {A method for analyzing the characteristics of turbulence responsible for radial heat transport is proposed. The method is based on the previously proposed hypotheses (to a great extent, confirmed experimentally) concerning the consistency of normalized pressure profiles in tokamak plasmas and the mechanism of internal transport barrier formation. Using the proposed approach, it is shown that, under an external action on the plasma, when the plasma heat flux onto the wall grows, the spectrum of turbulent modes broadens due to the excitation of modes with lower poloidal numbers m. Thus, in contrast to the conventional diffusion approach, the transport coefficient depends on the flux intensity. A mechanism of formation of internal transport barriers is proposed.},
doi = {10.1134/S1063780X16090087},
journal = {Plasma Physics Reports},
number = 9,
volume = 42,
place = {United States},
year = 2016,
month = 9
}
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