TITLE

A drift-magnetohydrodynamical fluid model of helical magnetic island equilibria in the pedestals of H-mode tokamak plasmas

AUTHOR(S)
Fitzpatrick, R.; Waelbroeck, F. L.
PUB. DATE
June 2010
SOURCE
Physics of Plasmas;Jun2010, Vol. 17 Issue 6, p062503
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
A drift-magnetohydrodynamical (MHD) fluid model is developed for an isolated, steady-state, helical magnetic island chain, embedded in the pedestal of a large aspect ratio, low-β, circular cross section, H-mode tokamak plasma, to which an externally generated, multiharmonic, static magnetic perturbation whose amplitude is sufficiently large to fully relax the pedestal toroidal ion flow is applied. The model is based on a set of single helicity, reduced, drift-MHD fluid equations which take into account neoclassical poloidal and toroidal flow damping, the perturbed bootstrap current, diamagnetic flows, anomalous cross-field diffusion, average magnetic-field line curvature, and coupling to drift-acoustic waves. These equations are solved analytically in a number of different ordering regimes by means of a systematic expansion in small quantities. For the case of a freely rotating island chain, the main aims of the calculation are to determine the chain’s phase velocity, and the sign and magnitude of the ion polarization term appearing in its Rutherford radial width evolution equation. For the case of a locked island chain, the main aims of the calculation are to determine the sign and magnitude of the polarization term.
ACCESSION #
51848466

 

Related Articles

  • Characteristics of magnetic island formation due to resistive interchange instability in helical plasma. Ueda, R.; Watanabe, K. Y.; Matsumoto, Y.; Itagaki, M.; Sato, M.; Oikawa, S. // Physics of Plasmas;May2014, Vol. 21 Issue 5, p052502-1 

    Focusing attention on the magnetic island formation, we investigate the characteristics of the resistive interchange magnetohydrodynamics instabilities, which would limit a high beta operational regime in helical type fusion reactors. An introduction of a new index, i.e., the ratio of the...

  • The physics of the International Thermonuclear Experimental Reactor FEAT. Campbell, D. J. // Physics of Plasmas;May2001, Vol. 8 Issue 5, p2041 

    The Intemational Thermonuclear Experimental Reactor FEAT design for a long-pulse tokamak burning plasma experiment (R = 6.2 m, a = 2 m, B = 5.3 T, I = 15 MA) is intended to achieve extended burn in inductively driven deuterium-tritium plasmas with the ratio of fusion power to auxiliary heating...

  • On limitations of the spectrogram in the representation of the amplitude of nonstationary fusion plasma signals. Figueiredo, António C. A.; Bizarro, João P. S. // Review of Scientific Instruments;Oct2006, Vol. 77 Issue 10, p10F509 

    The spectrogram capability to track the amplitude of signal components is discussed. A study using theoretical signal models shows that significant discrepancies may exist between the evolutions of the amplitude of a nonstationary signal component and of the magnitude of the corresponding...

  • Guiding center particle simulation of wide-orbit neoclassical transport. Bergmann, A.; Peeters, A. G.; Pinches, S. D. // Physics of Plasmas;Dec2001, Vol. 8 Issue 12, p5192 

    The neoclassical ion transport in a tokamak plasma with circular cross section is studied with guiding center particle simulations. A Monte Carlo model of pitch-angle scattering which includes momentum conservation is employed. The model includes the whole plasma inside closed flux surfaces, but...

  • Stability analysis of internal ideal modes in low-shear tokamaks. Wahlberg, C.; Graves, J. P. // Physics of Plasmas;Nov2007, Vol. 14 Issue 11, p110703 

    The stability of internal, ideal modes in tokamaks with low magnetic shear in the plasma core is analyzed. For equilibria with large aspect ratio, a parabolic pressure profile and a flat q profile in the core, an exact solution of the ideal magnetohydrodynamic (MHD) stability equations is found....

  • Structure of Global Tokamak Scalings. Dnestrovskij, Yu. N. // Plasma Physics Reports;Feb2002, Vol. 28 Issue 2, p166 

    In empirical tokamak scalings, not all of the standard engineering parameters are independent. Thus, the larger the tokamak, the higher the required plasma current and input power. Also, by using higher magnetic fields, it is possible to raise the plasma density. Instead of the plasma density,...

  • High-Q plasmas in the TFTR tokamak. Jassby, D. L.; Barnes, C. W.; Bell, M. G.; Bitter, M.; Boivin, R.; Bretz, N. L.; Budny, R. V.; Bush, C. E.; Dylla, H. F.; Efthimion, P. C.; Fredrickson, E. D.; Hawryluk, R. J.; Hill, K. W.; Hosea, J.; Hsuan, H.; Janos, A. C.; Jobes, F. C.; Johnson, D. W.; Johnson, L. C. // Physics of Fluids B: Plasma Physics;Aug91, Vol. 3 Issue 8, p2308 

    In the Tokamak Fusion Test Reactor (TFTR) [Plasma Phys. Controlled Fusion 26, 11 (1984) ], the highest neutron source strength S[sub n] and D-D fusion power gain Q[sub DD] are realized in the neutral-beam-fueled and heated "supershot" regime that occurs after extensive wall conditioning to...

  • Sawtooth studies with q-profile measurement on TFTR(abstract)[sup a]. Levinton, F.M.; Batha, S.H.; Yamada, M.; Zakharov, L.; Zarntorff, M.C. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p372 

    Measures the q profile for plasma equilibrium and theories of MHD instabilities in a Tokamak Fusion Test Reactor (TFTR). Measurement of diagnostic and accurate profiles.

  • Performance of the Tokamak Fusion Test Reactor bolometers. Schivell, J. // Review of Scientific Instruments;May85, Vol. 56 Issue 5, p972 

    For the past year we have been making use of a horizontally viewing 19-channel array and a bolometer which views a narrow cross-sectional slice of the plasma. More recently, we have also obtained results from a second, vertically viewing array. Software has been developed to translate the data...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

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

Try another library?
Sign out of this library

Other Topics