Nanosecond volume discharge in the non-stationary high-speed profiled channel flow

Abstract

The aim of the work is an experimental and numerical investigation of the interaction between the pulse volume discharge with a high-speed flow in the rectangular profiled channel (obstacle on the bottom wall). The special type of combined discharge—pulse volume discharge with preionization by an ultraviolet radiation from plasma sheets—is used. The flow around the obstacle influences the pulse discharge plasma distribution. The short-pulse initiation of a high power discharge leads to the effects observable in the time range up to millisecond. Ultrafast local heating of the medium with the formation of blast (shock) waves is carried out during the creation of a high nonequilibrium sub microsecond pulsed plasma. The duration of the shock-wave effect of the pulsed discharge is from 20 to 120 μs in supersonic and transonic flow. The spatially inhomogeneous distribution of energy input in a supersonic flow associates with the density lowest areas, which occur in a gas flow regime in a channel with an obstacle on the bottom. Discharge localization regions are sources of more intense wall surface local heating observed in the infrared range. A numerical calculation is carried out in order to match the calculated and experimental gas dynamical configurations.