TITLE

Drift-kinetic simulation of neoclassical transport with impurities in tokamaks

AUTHOR(S)
Kolesnikov, R. A.; Wang, W. X.; Hinton, F. L.; Rewoldt, G.; Tang, W. M.
PUB. DATE
February 2010
SOURCE
Physics of Plasmas;Feb2010, Vol. 17 Issue 2, p022506
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Plasmas in modern tokamak experiments contain a significant fraction of impurity ions in addition to the main deuterium background ions. A new multiple ion-species δf particle simulation capability has been developed to self-consistently study the nonlocal effects of impurities on neoclassical transport in toroidal plasmas. A new algorithm for an unlike-particle collision operator, including test-particle and conserving field-particle parts, is described. Effects of the carbon impurity on the main deuterium species heat flux as well as an ambipolar radial electric field in a National Spherical Torus Experiment (NSTX) [M. Ono, S. M. Kaye, Y.-K. M. Peng et al., Nucl. Fusion 40, 557 (2000)] configuration were studied. A difference between carbon poloidal rotation found from simulation and from conventional theoretical estimates has been investigated and was identified to be a nonlocal finite orbit effect. In the case of large-aspect ratio tokamak configurations with steep toroidal flow profiles, we propose a theoretical model to describe this nonlocal effect. The dominant mechanisms captured by the model are associated with ion parallel velocity modification due to steep toroidal flow and radial electric field profiles. We present simulation results for carbon poloidal velocity in NSTX. Comparisons with neoclassical theory are discussed.
ACCESSION #
48352273

 

Related Articles

  • The effect of the inductive electric field on ion poloidal rotation in all collisionality regimes for the primary ions in tokamaks. Chengkang Pan; Shaojie Wang // Physics of Plasmas;Nov2007, Vol. 14 Issue 11, p112516 

    The expression for the poloidal rotation velocity of the primary ions that is caused by the parallel inductive electric field in tokamaks and valid in all collisionality regimes is derived via the Hirshman-Sigmar moment approach. Also the expression of the collisional impurity ions poloidal...

  • Preparation of TFTR diagnostics for D–T break-even experiments. Johnson, L. C.; Manos, D. M.; Young, K. M. // Review of Scientific Instruments;Aug1988, Vol. 59 Issue 8, p1881 

    Although diagnostic systems for the tokamak fusion test reactor (TFTR) must be compatible with high-power experiments in deuterium-tritium (D-T) plasmas, it has been neither possible nor desirable to implement ail the required features during the early phases of the facility. The research plan,...

  • Absolute calibration of tokamak fusion test reactor neutron detectors for D-T plasma operation. Jassby, D.L.; Barnes, Cris W.; Johnson, L.C.; Roquemore, A.L.; Strachan, J.D.; Johnson, D.W.; Medley, S.S.; Young, K.M. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p891 

    Describes the calibration of the two most sensitive Tokamak Fusion Test Reactor (TFTR) fission-chamber detectors by a deuterium-tritium (D-T) neutron generator rotated once around the torus in each direction. Combination of uncertainty for determining fusion neutron rates; Calculation of the...

  • The poloidal distribution of type-III edge localized modes in the Mega-Ampère spherical tokamak (MAST). Antar, G. Y. // Physics of Plasmas;May2006, Vol. 13 Issue 5, p052509 

    This article describes the poloidal plasma particle distribution of type-III edge localized modes (ELMs) in the Mega-Ampère spherical tokamak [R.-J. Akers et al., Phys. Plasmas 9, 3919 (2002)]. A fast imaging camera with 10 μs exposure time is used to record the Dα light coming from the...

  • Downstream heat flux profile versus midplane T profile in tokamaks. Goldston, Robert J. // Physics of Plasmas;Jan2010, Vol. 17 Issue 1, p012503 

    The relationship between the midplane scrape-off-layer (SOL) electron temperature profile and the parallel heat flux profile at the divertor in tokamaks is investigated. A model is applied that takes into account anisotropic thermal diffusion in rectilinear geometry with constant density....

  • Testing the neutron attenuator based on 6LiH for ?-ray diagnostics of plasmas in the JET tokamak. Chugunov, I. N.; Shevelev, A. E.; Gin, D. B.; Naidenov, V. O.; Kiptily, V.; Edlington, T.; Syme, B. // Instruments & Experimental Techniques;Mar2008, Vol. 51 Issue 2, p166 

    A 6LiH attenuator of a neutron flux incident on a detector is used to reduce the ?-ray background induced by neutrons in the detector material. This attenuator has been tested during experiments with deuterium (DD) plasmas on the JET tokamak. A specimen of the neutron attenuator with dimensions...

  • Improved model for transport driven by drift modes in tokamaks. Halpern, Federico D.; Eriksson, Annika; Bateman, Glenn; Kritz, Arnold H.; Pankin, Alexei; Wolfe, Christopher M.; Weiland, Jan // Physics of Plasmas;Jan2008, Vol. 15 Issue 1, p012304 

    A comparison is made between two versions of the Weiland model for computing anomalous transport driven by drift modes such as the ion temperature gradient (ITG) and trapped electron mode (TEM) in tokamak plasmas. Both are quasilinear fluid models that include physical effects resulting from...

  • Simulations of global electrostatic microinstabilities in ASDEX Upgrade discharges. Bottino, A.; Peeters, A.G.; Sauter, O.; Vaclavik, J.; Villard, L. // Physics of Plasmas;Jan2004, Vol. 11 Issue 1, p198 

    Electrostatic microinstabilities in ion internal barrier (ITB) and H-mode discharges of the ASDEX Upgrade tokamak [O. Gruber, R. Arslanbekov, C. Atanasiu et al., Nucl. Fusion 41, 1369 (2001)] have been investigated with a full radius gyrokinetic code. The code models linear stability and...

  • Asymmetric radiation-induced toroidal flow and improved confinement in tokamaks. Singh, R.; Kaw, P. K.; Rogister, A. L.; Tangri, V. // Physics of Plasmas;Apr2006, Vol. 13 Issue 4, p042505 

    The role of impurity radiation in influencing the toroidal flow and radial electric fields (parameters critical for determining turbulent transport) has been studied on the edge of a tokamak plasma. It is demonstrated for the first time that the impurities distributed in an asymmetric...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics