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arXiv · 1712.02564

Numerical analysis of azimuthal rotating spokes in a crossed-field discharge plasma

R. Kawashima·K. Hara·K. Komurasaki
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Abstract

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$\times$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$\times$B direction with a phase velocity of 2,500 m/s, 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.

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R. Kawashima, K. Hara, K. Komurasaki. 2017-12-07. Numerical analysis of azimuthal rotating spokes in a crossed-field discharge plasma. https://doi.org/10.1088/1361-6595/aab39c

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