Particle pinch and collisionality in gyrokinetic simulations of tokamak plasma turbulence

Angioni, C.; Candy, J.; Fable, E.; Maslov, M.; Peeters, A. G.; Waltz, R. E.; Weisen, H.
June 2009
Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p060702
Academic Journal
The generic problem of how, in a turbulent plasma, the experimentally relevant conditions of a particle flux very close to the null are achieved, despite the presence of strong heat fluxes, is addressed. Nonlinear gyrokinetic simulations of plasma turbulence in tokamaks reveal a complex dependence of the particle flux as a function of the turbulent spatial scale and of the velocity space as collisionality is increased. At experimental values of collisionality, the particle flux is found close to the null, in agreement with the experiment, due to the balance between inward and outward contributions at small and large scales, respectively. These simulations provide full theoretical support to the prediction of a peaked density profile in a future nuclear fusion reactor.


Related Articles

  • Turbulent Ion Heating in a Plasma with Two Ion Species. Kuzora, I.V.; Silin, V.P.; Uryupin, S.A. // Plasma Physics Reports;Apr2004, Vol. 30 Issue 4, p307 

    A description of ion heating by ion-acoustic turbulence in a plasma containing two ion species of different charge-to-mass ratio is presented. It is shown that, when collisions between ions of different species are ignored, only one of the ion species is heated substantially while the...

  • Cross-machine comparison of resonant field amplification and resistive wall mode stabilization by plasma rotation. Reimerdes, H.; Hender, T. C.; Sabbagh, S. A.; Bialek, J. M.; Chu, M. S.; Garofalo, A. M.; Gryaznevich, M. P.; Howell, D. F.; Jackson, G. L.; La Haye, R. J.; Liu, Y. Q.; Menard, J. E.; Navratil, G. A.; Okabayashi, M.; Pinches, S. D.; Sontag, A. C.; Strait, E. J.; Zhu, W.; Bigi, M.; de Baar, M. // Physics of Plasmas;May2006, Vol. 13 Issue 5, p055704 

    Dedicated experiments in the DIII-D tokamak [J. L. Luxon, Nucl. Fusion, 42, 614 (2002)], the Joint European Torus (JET) [P. H. Rebut, R. J. Bickerton, and B. E. Keen, Nucl. Fusion 25, 1011 (1985)], and the National Spherical Torus Experiment (NSTX) [M. Ono, S. M. Kaye, Y.-K. M. Peng et al.,...

  • Intrinsic rotation driven by the electrostatic turbulence in up-down asymmetric toroidal plasmas. Camenen, Y.; Peeters, A. G.; Angioni, C.; Casson, F. J.; Hornsby, W. A.; Snodin, A. P.; Strintzi, D. // Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p062501 

    The transport of parallel momentum by small scale fluctuations is intrinsically linked to symmetry breaking in the direction of the magnetic field. In tokamaks, an up-down asymmetry in the equilibrium proves to be an efficient parallel symmetry breaking mechanism leading to the generation of a...

  • Large amplitude double layers in a positively charged dusty plasma with nonthermal electrons. Djebli, M.; Marif, H. // Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p063708 

    A pseudopotential approach is used to investigate large amplitude dust-acoustic solitary structures for a plasma composed of positively charged dust, cold electrons, and nonthermal hot electrons. Numerical investigation for an adiabatic situation is conducted to examine the existence region of...

  • Hydrogen atoms in Debye plasma environments. Paul, S.; Ho, Y. K. // Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p063302 

    Plasma-screening effects are investigated on hydrogen atoms embedded in weakly coupled plasmas. In the present context, bound state wave functions are introduced related to the screening Coulomb potential (Debye model) using the Ritz variation method. The bound energies are derived from an...

  • Mirror instability in space plasmas: Solitons and cnoidal waves. Istomin, Ya. N.; Pokhotelov, O. A.; Balikhin, M. A. // Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p062905 

    The nonlinear theory of magnetic mirror instability (MI) in space plasmas is revisited. The nonlinear dynamics of the MI is analyzed using the perpendicular plasma pressure balance condition and the drift kinetic equation for the ion distribution function as the starting point. In contrast with...

  • Oscillating two stream instability of electromagnetic pump in the ion cyclotron range of frequency in a plasma. Ahmad, Nafis; Tripathi, V. K.; Rafat, M.; Husain, Mudassir M. // Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p062308 

    An analytical formalism of oscillating two stream instability of a large amplitude electromagnetic wave in the ion cyclotron range of frequency in a plasma is developed. The instability produces electrostatic ion cyclotron sidebands and a driven low frequency mode. The nonlinear coupling arises...

  • On the estimation by Kadomtsev of coefficients of turbulent transport in magnetized plasma. Nedospasov, A. V. // Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p060501 

    The behavior of plasma in magnetic field is, as a rule, defined by nonlinear interaction of numerous oscillations and exhibits a complex turbulent pattern. Such state of plasma cannot described by linear and quasilinear theories. This paper reflects on the history of studying turbulence in...

  • New electromagnetic particle simulation code for the analysis of spacecraft-plasma interactions. Miyake, Yohei; Usui, Hideyuki // Physics of Plasmas;Jun2009, Vol. 16 Issue 6, p062904 

    A novel particle simulation code, the electromagnetic spacecraft environment simulator (EMSES), has been developed for the self-consistent analysis of spacecraft-plasma interactions on the full electromagnetic (EM) basis. EMSES includes several boundary treatments carefully coded for both...


Read the Article


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

Try another library?
Sign out of this library

Other Topics