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arXiv · 1802.07659

3D modelling of self-organized patterns of spots on anodes of DC glow discharge

M. S. Bieniek·P. G. C. Almeida·M. S. Benilov
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Abstract

Self-organized patterns of spots on a at metallic anode in a cylindrical glow dis- charge tube are simulated self-consistently. A standard model of a glow discharge is used, comprising conservation and transport equations for a single species of ion and electrons, written with the use of the drift-diffusion and local-field approximations, and the Poisson equation. The computation domain is the region from the anode to the discharge column; only processes in the near-anode region are considered. Multiple solutions, existing in the same range of discharge current and describing modes with and without anode spots, are computed by means of a stationary solver. The computed spots exhibited unexpected behavior. A reversal of the local anode current density in the middle of each of the spots was found, i.e. mini-cathodes are formed inside the spots. The solutions do not fit into the conventional pattern of self-organization in bistable nonlinear dissipative systems; e.g. the modes are not joined by bifurcations.

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M. S. Bieniek, P. G. C. Almeida, M. S. Benilov. 2018-02-21. 3D modelling of self-organized patterns of spots on anodes of DC glow discharge. https://doi.org/10.1088/1361-6595/aac0e9

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