Plasma flow measurements along the presheath of a magnetized plasma
Plasma flow measurements along the presheath of a magnetized plasma
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沿磁化等离子体预护套的等离子体流测量
DOI：
10.1063/1.859039
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
R. Conn
中科院分区：
文献类型：
--
作者：
K. Chung;I. Hutchinson;B. LaBombard;R. Conn
在加州大学洛杉矶分校的双鱼座设施中，使用两种类型的定向电‘’马赫‘’探头进行了预健康中的等离子体流动测量[J.Nucl。马特。121,277(1984)]。开发了一种快速扫描多功能探头组合，它可以同时作为磁化马赫探头、非磁化马赫探头(其特征探头尺寸分别大于和小于离子回旋半径)和发射探头来工作。通过在等离子体柱的中心插入一个小物体来研究前置路径。根据流体和动力学理论推导出等离子体流动速度、密度和位势沿预生程的变化。对磁化探头和非磁化探头的马赫数进行了比较。将∼-0.5nmiD-⊥量级的剪切粘度加入到沿前向的交叉场输运中似乎是模拟结果的最好方法。结果表明，交叉场扩散系数(D⊥)与B−1/2成正比，随磁化强度的增大而增大。
Plasma flow measurements in the presheath have been performed using two types of directional electric ‘‘Mach’’ probes, in the PISCES facility at UCLA [J. Nucl. Mater. 121, 277 (1984)]. A fast scanning versatile probe combination has been developed, which operates simultaneously as a ‘‘magnetized’’ Mach probe, an ‘‘unmagnetized’’ Mach probe (with characteristic probe size greater than and smaller than ion gyroradius, respectively), and an emissive probe. Presheaths have been investigated by inserting a small object at the center of the plasma column. Variations in plasma flow velocity, density, and potential along the presheath have been deduced by fluid and kinetic theories. A comparison is made between Mach numbers obtained from the magnetized probe and the unmagnetized probe. Incorporation of shear viscosity of order ∼0.5nmiD⊥ in the cross‐field transport along the presheath seems best to model the results. The cross‐field diffusivity (D⊥) is found to scale approximately proportional to B−1/2, with magn...