NUMERICAL INVESTIGATION OF THE ELECTROPHYSICAL AND PLASMA-CHEMICAL MECHANISMS OF FORMATION OF A NEGATIVE STREAMER OF AN IMPULSE HIGH-VOLTAGE DISCHARGE IN AN AIR BUBBLE IN WATER

The article presents the results of numerical modeling of the formation of a negative streamer of an impulse high-voltage discharge in an air bubble inside the water. The distributions of the electric field intensity, potential, current density, electron temperature, and concentrations of charged and excited particles are shown. The calculations indicate that the streamer evolves into a highly conductive channel, causing a sharp increase in the electric field strength in the water. The process of development of the conduction current in an air bubble and the displacement current in water is demonstrated, taking into account the “air (plasma) − water interface”. The obtained results provide a basis for optimizing the parameters of nanosecond discharges in air bubbles in water and justify significant interest for further experimental and theoretical investigations.