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Indexed by:期刊论文

Date of Publication:2013-01-01

Journal:PHYSICS OF PLASMAS

Included Journals:SCIE、EI

Volume:20

Issue:1

ISSN No.:1070-664X

Abstract:Roles of poloidal rotation in stabilizing the m/n = 1/1 kink-tearing mode and exciting its high-order harmonic tearing modes are numerically investigated by using a reduced magnetohydrodynamic ;model. It is found that the high-order harmonic tearing modes, such as m/n = 2/2, m/n = 3/3, or even much higher-m harmonics, can be destabilized so significantly by rotation shear as to be more unstable than or comparable to the m/n = 1/1 mode. Moreover, the short wave-length KelvinHelmholtz (KH) instabilities can be excited in the large rotation shear regime. The scaling power laws of the linear growth rate for each harmonic mode in different rotation shear regimes are verified by the previous relevant theoretical results based on the non-constant-psi and constant-psi behavior categories in tearing modes. During the nonlinear evolution, the m/n = 2/2 mode dominated phase first appears and then is followed by the m/n = 1/1 mode dominated nonlinear phase instead. Afterward, some smaller sub-islands due to the high-order harmonics are produced in the large irregular m = 1 crescent-shaped island, and then a coalescence process of turbulent island chains occurs before the decay phase. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4789381]