Numerical analysis of azimuthal rotating spokes in a crossed-field discharge plasma
Numerical analysis of azimuthal rotating spokes in a crossed-field discharge plasma
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DOI：
10.1088/1361-6595/aab39c
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发表时间：
2017-12
影响因子：
3.8
通讯作者：
R. Kawashima;K. Hara;K. Komurasaki
中科院分区：
文献类型：
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作者：
R. Kawashima;K. Hara;K. Komurasaki
通过二维数值模拟，得到了交叉场放电等离子体中的低频旋转轮辐。粒子-流体混合模型被用来模拟类似于霍尔推进器结构的等离子体流动。有报道称，电子流体的漂移-扩散近似在求解势场时会导致病态矩阵，这是因为电子在磁场和E×B漂移方向上的迁移率不同。在本文中，我们使用了一种双曲线方法，它使计算变得稳定，即电子流体模型更好地迭代收敛。我们的模拟结果表明，相干旋转结构沿E×B方向传播，相速度为2500m S−1，这与实验数据一致。由数值模拟得到的相速度与由梯度漂移不稳定性的色散关系所预测的相速度符合得很好。
Low-frequency rotating spokes are obtained in a cross-field discharge plasma using two-dimensional numerical simulations. A particle-fluid hybrid model is used to model the plasma flow in a configuration similar to a Hall thruster. It has been reported that the drift-diffusion approximation for an electron fluid results in an ill-conditioned matrix when solving for the potential because of the differences in the electron mobilities across the magnetic field and in the direction of the E × B drift. In this paper, we employ a hyperbolic approach that enables stable calculation, namely, better iterative convergence of the electron fluid model. Our simulation results show a coherent rotating structure propagating in the E × B direction with a phase velocity of 2500 m s−1, which agrees with experimental data. The phase velocity obtained from the numerical simulations shows good agreement with that predicted by the dispersion relation of the gradient drift instability.