相干结构Blob在HT-7托卡马克边界的传播  

Propagation of Blob in boundary of HT-7 tokamak

作　　者：颜宁[1] 张炜[1] 常加峰[1] 明廷凤[1] 丁斯晔[1] 

机构地区：[1]中国科学院等离子体物理研究所,合肥230031

出　　处：《强激光与粒子束》2011年第10期2640-2644,共5页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(10675124)

摘　　要：相干结构Blob的间歇爆发清晰地反映在HT-7托卡马克边界探针的离子饱和流信号中,Blob的径向传播在近刮削层堆积出一个温度和密度的平台区,使密度和温度分布偏离了指数分布。条件平均方法提示了间歇脉冲结构空间分布的均匀性,Blob内部等离子体参数远高于背景等离子体参数,并且呈现出涡旋的形态。最后闭合磁面附近的数据显示,Blob的间歇爆发导致了边界约50%的粒子输运和能量输运。实验结果表明:相干结构在剪切层受到了扭曲,在刮削层区域沿离子的逆磁漂移方向传播。Intermittent characteristics of turbulence induced by coherent structures（Blob） are manifested clearly on the Langmuir probe signal of HT-7 tokamak.With conditional analysis,asymmetric characteristics of the intermittent bursts are demonstrated.The parameter of plasma inside the Blob is larger than the background plasma parameter.Due to the radial propagation of the coherent structures,the particle density and temperature profiles in the scrape-off layer（SOL） are non-exponential and flat away from the last closed flux surface（LCFS）.Around the LCFS,large burst fluctuations are responsible for about 50% of the total transport.These experimental finds may imply that the coherent structures are distorted by the developed shear flow in the shear layer.In SOL region,the coherent structures propagate in the direction of ion diamagnetic drift.

关 键 词：间歇爆发 相干结构 漂移速度 Blob空间尺度 去相关 剪切层 

分 类 号：O532.26[理学—等离子体物理] O433.1[理学—物理]