A theoretical model for an electrical discharge in a
cavitating
liquid is developed and compared with experiments for the optimization
of the water treatment device. The calculations based on solution
of the Noltingk—Neppiras equation support the hypothesis that
the electric field promotes the formation of vapor microchannels inside
a liquid gap between the electrodes, where at a low gas pressure Paschen’s
conditions of rupture and abnormal glow discharge maintenance in those
microchannels are fulfilled. Theoretical analysis of the cavitation
processes and the discharge formation processes is in qualitative
agreement with the experimental data obtained in this work in a water
treatment device using a hydrodynamic emitter. The following graphic
illustrates the experimental setup: (1) feeding tank, (2) hydrodynamic
emitter, (3) zone of cavitation inside the plasma reactor, (4) high-frequency
generator of electric impulses, and (5) outlet.