Edge Plasma Radial Profiles and Confinement Property on the HL-1M Tokamak

摘要

The relation of edge plasma radial profiles and confinement property was described by means of the measurement results with a Mach/Langmuir mixed probe array on the HL-1M Tokamak. The probe array can measure not only parallel flows and the flow perpendicular to the magnetic field but the radial and the poloidal electric field E_r and E_θ as well. Measurements of the edge fluctuations, velocities of the toroidal and the poloidal and electric field have been carried out on both of scrap-off layer (SOL) and the boundary region of HL-1M under the condition of Ohmic, Lower Hybrid Current Drive (LHCD), Supersonic Molecular Beam Injection (SMBI), Multi-shot Pellet Injection (MPI) and Neutral Beam Injection (NBI) discharges. The results show that the suppressions of the fluctuations are related to poloidal rotations produced by different discharges in improved particle confinement mode. The changes of the radial and poloidal electric field is generated simultaneously and becomes more negative at the tokamak plasma edge and the sheared poloidal flow is related to the reduction in fluctuation level. The poloidal rotation velocity is mainly dominated by the E-vector * B-vector drift.