Abstract
Analysis of global magnetohydrodynamic (MHD) instabilities in the L-2M stellarator (Prokhorov General Physics Institute, Russian Academy of Sciences) is presented. The properties of free-boundary equilibria states are outlined, the stability conditions for small-scale modes are briefly discussed, and the number of trapped particles is estimated. All the magnetic configurations under study are stable against ballooning modes. It is shown that global ideal internal MHD modes can be found reliably only in Mercier unstable plasmas. In plasma that is stable with respect to the Mercier criterion, global unstable modes that are localized in the vicinity of the free plasma boundary and are not associated with any rational magnetic surface inside the plasma (the so-called peeling modes) can be found. The radial structure of all perturbations under study is almost entirely determined by the poloidal coupling of harmonics. The results of calculations are compared with the available experimental data.
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References
V. V. Abrakov, D. K. Akulina, Eh. D. Andryukhina, G. M. Batanov, M. S. Berezhetskij, I. S. Danilkin, N. P. Donskaya, O. I. Fedyanin, G. A. Gladkov, S. E. Grebenshchikov, J. H. Harris, N. K. Kharchev, Yu. V. Kholnov, L. V. Kolik, L. M. Kovrizhnykh, et al., Nucl. Fusion 37, 233 (1997).
N. K. Kharchev, G. M. Batanov, M. S. Berezhetskii, V. D. Borzosekov, O. I. Fedyanin, S. E. Grebenshchikov, I. A. Grishina, Yu. V. Kholnov, L. V. Kolik, E.M. Konchekov, L. M. Kovrizhnykh, N. F. Larionova, D. V. Malakhov, A. I. Meshcheryakov, A. E. Petrov, et al., Plasma Fusion Res. 6, 2405142 (2011).
U. Stroth, M. Murakami, R. A. Dory, H. Yamada, S. Okamura, F. Sano, and T. Obiki, Nucl. Fusion 36, 1063 (1996).
C. Nuehrenberg, in Proceedings of the 30th EPS Conference on Controlled Fusion and Plasma Physics, St. Petersburg, 2003, ECA 27A, P-1.16 (2003).
S. P. Hirshman and J. C. Witson, Phys. Fluids 26, 3553 (1983).
S. P. Hirshman, W. I. Rij, and P. Merkel, Comput. Phys. Commun. 43, 143 (1986).
M. I. Mikhailov, V. D. Shafranov, M. Drevlyak, J. Nürenberg, S. E. Grebenshchikov, A. B. Kuznetsov, and S. V. Shchepetov, Plasma Phys. Rep. 37, 338 (2011).
A. B. Kuznetsov and S. V. Shchepetov, Nucl. Fusion 36, 1097 (1996).
L. M. Kovrizhnykh and S. V. Shchepetov, Sov. J. Plasma Phys. 6, 533 (1980).
D. Lortz, Nucl. Fusion 15, 49 (1975).
N. Nakajima, in Proceedings of the 18th IAEA Fusion Energy Conference, Sorrento, 2000 (IAEA, Vienna, 2001), Paper THP2/14.
M. I. Mikhailov, S. V. Shchepetov, M. Drevlak, C. Nürenberg, and J. Nürenberg, Plasma Phys. Rep. 40, 781 (2014).
S. V. Shchepetov, Yu. V. Kholnov, O. I. Fedyanin, A. B. Kuznetsov, D. G. Vasilkov, D. K. Akulina, G. M. Batanov, G. A. Gladkov, S. E. Grebenshchikov, and A. I. Meshcheryakov, Plasma Phys. Controlled Fusion 50, 045001 (2008).
S. V. Shchepetov, Yu. V. Khol’nov, and D. G. Vasil’kov, Plasma Phys. Rep. 39, 130 (2013).
D. G. Vasil’kov, Yu. V. Khol’nov, and S. V. Shchepetov, Plasma Phys. Rep. 39, 615 (2013).
C. Schwab, Phys. Fluids 5, 3195 (1993).
R. H. Fowler, J. A. Rome, and J. F. Lyon, Phys. Fluids 28, 338 (1985).
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Original Russian Text © M.I. Mikhailov, S.V. Shchepetov, C. Nührenberg, J. Nührenberg, 2015, published in Fizika Plazmy, 2015, Vol. 41, No. 12, pp. 1096–1102.
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Mikhailov, M.I., Shchepetov, S.V., Nührenberg, C. et al. Global magnetohydrodynamic instabilities in the L-2M stellarator. Plasma Phys. Rep. 41, 1016–1022 (2015). https://doi.org/10.1134/S1063780X15120107
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DOI: https://doi.org/10.1134/S1063780X15120107