Finite Element Modelling of Fireballs in Low Pressure Gas Discharges

C. Speer, J. Gruenwald, J. Seebacher, and A. Kendl
University of Innsbruck
Institute for Ion Physics and Applied Physics
Innsbruck, Austria

In the Double-Plasma (DP) device at Innsbruck University the formation of plasma fireballs is investigated. Under certain conditions such a fireball evolves in front of a positively biased electrode, which is surrounded by a weakly ionized background plasma. A complete theoretical model is up to now not available.

In the present work the current experimental set up at Innsbruck University has been simulated with the plasma fluid model, which is part of the COMSOL Multiphysics code package. If the additional spherical anode is put inside the chamber in the simulations a shining sphere can be observed, which qualitatively agrees with the experimentally seen object.