HL-2A装置边缘扰动特性观测

Observation of edge fluctuation characteristics on the HL-2A tokamak

用中平面往复快速扫描6探针组观测HL-2A装置边缘等离子体的扰动特性。在一次放电中能测量到边缘等离子体参数的时空分布及其涨落量,雷诺胁强与极向流和带状流的关系,以及静电涨落驱动的粒子通量和热通量的径向变化。在多发弹丸注入(MPI)和多脉冲超声分子束注入(SMBI)条件下,研究了边缘参数的涨落和相关特性。实验结果表明:SMBI和MPI等注入手段改变了边缘的扰动特性;雷诺胁强的径向梯度可以驱动带状流,抑制湍流输运。

The edge plasma fluctuation characteristics are studied by the reciprocating fast scanning 6-probes in the boundary region of the HL-2A tokamak. The probes can be applied to measure, simultaneously, the temporal and spatial profiles of the edge plasma parameters, the relationship of Reynolds stress with the poloidal flow and the zonal flows, the changes of radial particle flux and radial heat flow in one discharge. These parameters are used to analyze edge turbulence and coherency under the condition of multi-pellet injection （MPI） and supersonic molecular beam injection （SMBI）. The results suggest that SMBI and MPI can influence the edge fluctuation characteristics, the radial gradient of Reynolds stress is able to drive zonal flows, as well as the turbulence and the transport may be suppressed.