Discontinuities dynamics after the interaction of a plane shock wave with pulse volume discharge

Abstract

The dynamics of the nanosecond combined volume discharge radiation in the air flow with the plane shock wave was studied. Shock wave with Mach number 1.9-4.5 was passing through the discharge chamber and coming out of it while the electric pulse was switched on. The radiation spectra and the discharge currents were registered in the air pressure range 10-150 Torr, a pulsed voltage of 25 kV, and an electric current ∼1 kA. It is shown that the electric current duration depends on shock wave position relative to the discharge gap and does not exceed 500 ns at various conditions. As a result of discharge energy input, the shock breakdown occurs with the formation of shock waves and contact surfaces. The high-speed shadow imaging was used to study the flow evolution after the discharge pulse. The experimental data on shock waves and contact surfaces positions is compared with numerically calculated positions, making it possible to determine the amount of thermal energy release during the discharge electric current time.