Speaker
Dr
Lai Wei
(Dalian University of Technology)
Description
Basic features of the multiscale interaction between drift tearing modes (TM) and ion temperature gradient (ITG) modes are studied by using an electromagnetic Landau fluid model in a slab geometry. It is observed that the energy spectra with respect to wavenumbers become broader during the transition phase from ITG-dominated stage to TM-dominated stage. Accompanied with the fast growth of magnetic island, the frequency of TM/ITG with long/short wavelength fluctuations in the electron/ion diamagnetic direction decreases/increases respectively. The decrease of the TM frequency is identified to result from the effect of the profile flattening in the vicinity of magnetic island, while the increase of the frequencies of ITG fluctuations is mainly due to the eigenmode transition of ITG induced by the large scale zonal flow and zonal current related to the drift TM. Roles of zonal current induced by the ITG fluctuations in the instability of drift TM are also analyzed. Finally, the electromagnetic transport features in the vicinity of magnetic island are discussed.
Primary author
Dr
Lai Wei
(Dalian University of Technology)
