A three-tip array is used in the HL-2A tokamak to investigate the spectral characteristics of electrostatic turbulence inside the last closed flux surface (LCFS) about 5 cm. Two-point correlation techniques are used...A three-tip array is used in the HL-2A tokamak to investigate the spectral characteristics of electrostatic turbulence inside the last closed flux surface (LCFS) about 5 cm. Two-point correlation techniques are used to analysis the turbulence structure. It is found that the drift wave turbulence mainly is composed of low-frequency and long wavelength wave packets. The poloidal propagation is mainly in electron-diamagnetic direction, sometimes it propagates in ion-diamagnetic direction, which is influenced by Doppler-frequency shift. The radial propagation velocity is outward and the sizeable fraction of the poloidal velocity, implying that the radial mode plays an important role in the cross field transport.展开更多
基金Supported by National Natural Science Foundation of China (10675041) First authors would give thanks to the HL-2A team for steady state discharges.
文摘A three-tip array is used in the HL-2A tokamak to investigate the spectral characteristics of electrostatic turbulence inside the last closed flux surface (LCFS) about 5 cm. Two-point correlation techniques are used to analysis the turbulence structure. It is found that the drift wave turbulence mainly is composed of low-frequency and long wavelength wave packets. The poloidal propagation is mainly in electron-diamagnetic direction, sometimes it propagates in ion-diamagnetic direction, which is influenced by Doppler-frequency shift. The radial propagation velocity is outward and the sizeable fraction of the poloidal velocity, implying that the radial mode plays an important role in the cross field transport.