Numerical study of transient processes in a corona dc microdischarge

An extended fluid model is formulated that describes a corona microdischarge at atmospheric pressure in argon, taking into account the heating of the cathode-tip. Numerical calculations have been carried out, demonstrating two main modes of the negative corona: repetitively pulsed and glow discharge mode. For both modes, all the main parameters of the corona discharge plasma were obtained. It is shown that the appearance of Trichel pulses is in many respects similar to the transition from the Townsend to the glow discharge mode and is similar to self-oscillations manifested in a classical discharge with flat electrodes.