Parameters of turbulent structures at the periphery of the FT-2 tokamak

  • S. V. Shatalin
  • E. O. Vekshina
  • J. Vicente
  • P. V. Vazhnov
  • L. A. Esipov
  • S. I. Lashkul
  • A. V. Sidorov


Results are presented from probe measurements carried out in the scrape-off layer of the FT-2 tokamak in the course of additional lower hybrid heating, during which an L-H transition was observed. The objective of this study was to obtain information on the parameters of blobs-turbulent structures with enhanced plasma density. The measurements were performed not only on the low-field side of the torus, but also on the high-field side, which is still poorly studied. Coherent structures with radial velocities directed both toward the vessel wall and into the plasma column were revealed at the tokamak periphery. Blobs propagating toward the vessel wall were found to prevail both before and after the L-H transition. The average radial velocity of blobs in the L- and H-modes was determined experimentally. The dependence of the radial blob velocity on the transverse size and density of the structure agrees with the ballooning mode model. It is found that the average value of the poloidal blob velocity is four to five times higher than the average radial velocity. The results of measurements carried out on both sides of the torus indicate the presence of internal poloidal polarization of blobs. The average drift velocity of such polarized structures is directed toward the vessel wall. The L-H transition is accompanied by a reduction in the radial velocity. At the same time, the average plasma density inside the structures observed on the low-field side increases appreciably during the transition. The obtained dependences of the radial blob velocity on the plasma density inside the structure generally agree with predictions of the ballooning mode model.


Plasma Physic Report Turbulent Structure Divertor Plate Blob Size High Field Side 
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  1. 1.
    S. I. Krasheninnikov, Phys. Lett. A 283, 368 (2001).ADSCrossRefGoogle Scholar
  2. 2.
    D. A. D’Ippolito, J. R. Myra, and S. I. Krasheninnikov, Phys. Plasmas 9, 222 (2002).ADSCrossRefGoogle Scholar
  3. 3.
    S. I. Krasheninnikov, D. A. D’Ippolito, and J. R. Myra, J. Plasma Phys. 74, 769 (2008).CrossRefGoogle Scholar
  4. 4.
    J. R. Myra and D. A. D’Ippolito, Phys. Plasmas 12, 092511 (2005).ADSCrossRefGoogle Scholar
  5. 5.
    O. E. Garcia, N. H. Bian, V. Naulin, et al., Phys. Plasmas 12, 090701 (2005).ADSCrossRefGoogle Scholar
  6. 6.
    V. Rozhansky and A. Kirk, Plasma Phys. Controlled Fusion 50, 025008 (2008).ADSCrossRefGoogle Scholar
  7. 7.
    S. I. Lashkul, V. N. Budnikov, A. D. Gurchenko, et al., Czech. J. Phys. 52, 1149 (2002).ADSCrossRefGoogle Scholar
  8. 8.
    A. N. Levitskii, I. E. Sakharov, and S. V. Shatalin, Prib. Tekh. Eksp., No. 5, 153 (1992).Google Scholar
  9. 9.
    S. V. Shatalin, E. O. Vekshina, P. R. Goncharov, et al., Fiz. Plazmy 30, 398 (2004) [Plasma Phys. Rep. 30, 363 (2004)].Google Scholar
  10. 10.
    S. V. Shatalin, A. V. Pavlov, A. Yu. Popov, et al., Fiz. Plazmy 33, 195 (2007) [Plasma Phys. Rep. 33, 169 (2007)].Google Scholar
  11. 11.
    S. I. Lashkul, A. B. Altukhov, A. D. Gurchenko, et al., in Proceedings of the 30th EPS Conference on Controlled Fusion and Plasma Physics, St. Petersburg, 2003, ECA 27A, P–3.151 (2003).Google Scholar
  12. 12.
    N. N. Skvortsova, V. Yu. Korolev, G. M. Batanov, et al., Plasma Phys. Controlled Fusion 48, A393 (2006).ADSCrossRefGoogle Scholar
  13. 13.
    G. S. Kirnev, V. P. Budaev, S. A. Grashin, et al., Nucl. Fusion 45, 459 (2005).ADSCrossRefGoogle Scholar
  14. 14.
    A. V. Filippas, R. D. Bengston, G. X. Li, et al., Phys. Plasmas 2, 839 (1995).ADSCrossRefGoogle Scholar
  15. 15.
    D. L. Rudakov, J. A. Boedo, R. A. Moyer, et al., Plasma Phys. Controlled Fusion 44, 717 (2002).ADSCrossRefGoogle Scholar
  16. 16.
    A. Schmid, A. Herrmann, and H. W. Muller, Plasma Phys. Controlled Fusion 50, 045007 (2008).ADSCrossRefGoogle Scholar
  17. 17.
    N. Asakura, H. Kawashima, N. Ohno, et al., J. Phys., Conf. Ser 123, 012009 (2008).ADSCrossRefGoogle Scholar
  18. 18.
    S. I. Lashkul, S. V. Shatalin, P. V. Vazhnov, et al., in Proceedings of the 35th EPS Conference on Plasma Physics, Hersonissos, 2008, ECA 32D, P4–043 (2008).Google Scholar

Copyright information

© Pleiades Publishing, Ltd. 2011

Authors and Affiliations

  • S. V. Shatalin
    • 1
  • E. O. Vekshina
    • 1
  • J. Vicente
    • 1
  • P. V. Vazhnov
    • 1
  • L. A. Esipov
    • 2
  • S. I. Lashkul
    • 2
  • A. V. Sidorov
    • 2
  1. 1.St. Petersburg State Polytechnical UniversitySt. PetersburgRussia
  2. 2.Ioffe Physical-Technical InstituteRussian Academy of SciencesSt. PetersburgRussia

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