This paper presents a review of investigations detailed spatial and temporal structures high-voltage pulsed nanosecond discharges in the form fast ionization waves. The most distinctive features this type discharge are high propagation velocity (109-1010 cm s-1), good reproducibility parameters at moderate (tens hertz) repetition rate homogeneity over large gas volume. was initiated by voltage pulses negative polarity with an amplitude 10-15 kV, duration half maximum 25 ns rise time front...

Abstract This paper presents an overview of experimental and numerical investigations the nonequilibrium cold plasma generated under high overvoltage further usage this for plasma-assisted combustion. Here, two different types discharge are considered: a streamer pressure so-called fast ionization wave (FIW) at low pressure. The comprehensive investigation processes alkane slow oxidation in mixtures with oxygen air nanosecond uniform has been performed. kinetics measured from methane to...

A detailed study of gas breakdown in the form a fast ionization wave has been carried out. Measurements charge distribution dynamics and spectroscopic registration , ) excited levels have performed simultaneously air pressure range 0.1-16 Torr. method to obtain longitudinal component electric field front electron density following it is proposed. This includes registration, taking into account space sensitivity function detector. The coupled computational procedure inverse problem solving...

Slow oxidation of n-butane and n-decane in lean mixtures with oxygen under the action a nanosecond pulsed discharge has been experimentally investigated. The was excited by 25 ns pulses an amplitude 22 kV on high-voltage electrode repetition frequency 40 Hz 20 cm long quartz tube. initial pressure varied within range from 0.8 to 10 Torr. energy input measured. radiation intensities following molecular bands have measured time-resolved integral modes: , OH(A2 Σ, v' = 0 → X2 Π, v'' 0), CO(B1...

The spatio-temporal evolution of electric parameters plasma and emission produced by high-voltage periodic pulsed discharge has been studied. was initiated voltage pulses 13.5 kV amplitude, 25 ns duration 6 rise time with a repetition frequency 40 Hz in molecular nitrogen at pressure 5 Torr. Differences between characteristics for positive negative polarities the pulse investigated. net electrical charge measured calibrated capacitive gauge moving along tube. Time-resolved fields electron...

High-voltage nanosecond discharge at moderate pressures develops in the form of a fast ionization wave. High electric field front produces high-energy electrons and supports uniform preionization. The creates spatially highly nonequilibrium plasma with dominant excitation electronic levels during tens hundreds nanoseconds. development is traced using emission second positive system molecular nitrogen. ICCD images propagation air are presented.

The charge density per unit length, the longitudinal component of electric field and electron concentration behind front fast ionization wave, initiated by a nanosecond voltage pulse negative polarity in air, N2 H2, are reconstructed pressure range 1-24 Torr. breakdown initiation from high-voltage electrode is investigated. accumulation positive vicinity cathode at initial moment time discharge development revealed; dependence conduction current through determined. Energy branching analysed...

This paper presents a hybrid interferometric system designed to measure the surface velocity of tested specimens in shock-wave experiments. The integrates All-Fiber Velocity Interferometer System for Any Reflector (AFVISAR) and Photonic Doppler Velocimeter (PDV) channels using single probing one point under study. design allows same optical signal containing frequency shift be processed by AFVISAR PDV independent devices. has been dynamic experiments provides measurement accuracy at least...

In case of fire, combustible materials and products made on their basis have a decisive role in the development combustion, formation spread foreground risks. Normative legal documents restrict use fire hazardous materials, but it is impossible to exclude completely. addition flame high temperatures are formed smoke toxic gaseous combustion. The most common polyvinyl chloride - one whose production volumes only increased recent years. course this work, an express method has been developed...

The Doppler-signal processing method based on two integral convolutions with respect to approximate Doppler phase, φ(t), being a variable is introduced. While reducing the noise, these transforms produce first harmonic, S1‖(t), and its quadrature complement, S1⊥(t). complex s1(t)=S1‖(t)+iS1⊥(t), makes it possible find new approximation of both signal frequency ωD(t) phase as well rms error, χωD(t), used regularize solution. iterative procedure estimate ωD(t), which converges in mean...