Release Time:2019-03-13  Hits:

Indexed by: Journal Article

Date of Publication: 2016-05-01

Journal: NUCLEAR FUSION

Included Journals: Scopus、EI、SCIE

Volume: 56

Issue: 5

ISSN: 0029-5515

Key Words: internal transport harrier; ion temperature gradient mode; flow shear

Abstract: Ion internal transport barriers (iITBs) arc first observed in neutral beam injection (NBI) heated plasmas at the I HL-2A tokamak, The position of the barrier foot, in the stationary state, coincides with the q = 1 surface within its uncertainty of measurement. iITBs can develop more easily at the beginning of NBI heating. Also, iITBs are unstable for the sawtooth plasma, Simulations reveal that the thermal diffusivity of ions (x) inside the barrier can be as low as the neoclassical level. It is observed that the flow shear in the stationary iITB state reaches the level required for suppressing the ion temperature gradient mode instability, which indicates the important role of flow shear in sustaining the iITB,