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This paper presents the research data on the dynamics of a repetitive pulsed discharge as a source of plasma jets in atmospheric pressure air and on the conditions under which the discharge produces apokamp–plasma jets ejected from the bending point of the discharge channel with no gas supply through the discharge region. The data suggest that the formation of apokamps requires the application of a large number of voltage pulses to sharp-ended electrodes at a repetition frequency of several to tens of kilohertz. Before an apokamp starts developing, the apokamp-initiating discharge passes through a spark stage and then becomes diffuse. Next, at the site of electric field amplification, the discharge channel gives rise to a bright branch from which plasma bullets escape with a velocity of ∼200 km/s. The images of different discharge and apokamp stages are presented.

The use of stationary solvers instead of approximate solution methods or time-dependent solvers, which are standard tools in gas discharge modeling, allows one to develop a very fast and robust numerical model for studying the time-averaged characteristics of dc corona discharges. Such an approach is applied to dc corona discharges in point-plane gaps in ambient air. A wide range of currents of both voltage polarities and various gap lengths are investigated, and the simulation results are validated by comparing the computed current-voltage characteristics and spatial distributions of the radiation intensity with experimental results. Specific features of the numerical and experimental results at both polarities are discussed.

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