论文标题
方位角结构和湍流运输
Azimuthal structures and turbulent transport in Penning discharge
论文作者
论文摘要
用轴向磁场的2D3V径向 - 齐路PIC/MCC模型研究了圆柱笔排放中的方位角结构。由于电子的轴向注入，由于电离，因此由电离得到了自愿的支撑。结果表明，稳态排放可以在具有不同类型的方位角结构的两个不同类型的方向上支持。机制之间的过渡受到排放的能量输入机理的控制。在第一个制度（注入电子的低能）中，具有明显的$ M = 1 $辐条活动，功率输入由径向电流和自洽电场引起的能量吸收主导。在另一个方向（注入电子的较高能量）中，具有普遍的小尺度$ m> 1 $螺旋结构，并且较低的异常传输值，沉积到放电的总能量较低，并且主要是由于轴向电子束的动能直接输入。我们表明，大型（M = 1）的辐条和小规模结构是由于Simon-HOH和由电场，密度梯度和碰撞驱动的较低的杂种不稳定性而发生的。我们表明，辐条频率遵循平衡离子旋转频率。
Azimuthal structures in cylindrical Penning discharge are studied with 2D3V radial-azimuthal PIC/MCC model with the axial magnetic field. The discharge is self-consistently supported by ionization due to the axial injection of electrons. It is shown that the steady-state discharge can be supported in two different regimes with different type of observed azimuthal structures. The transition between the regimes is controlled by the mechanism of the energy input to the discharge. In the first regime (low energy of the injected electrons), with the pronounced $m=1$ spoke activity, the power input is dominated by the energy absorption due to the radial current and self-consistent electric field. In the other regime (higher energy of the injected electrons), with prevalent small scale $m>1$ spiral structures, and the lower values of the anomalous transport, the total energy deposited to the discharge is lower and is mostly due to the direct input of the kinetic energy from the axial electron beam. We show that the large (m=1) spoke and small scale structures occur as a result of Simon-Hoh and lower hybrid instabilities driven by the electric field, density gradient, and collisions. We show that the spoke frequency follows the equilibrium ion rotation frequency.
