Vapor-air discharges between electrolytic cathode and metal anode at atmospheric pressure

Experimental investigation is performed of the structures and electrical characteristics of vapor-air discharges between a metal (solid, hollow, pointed) anode and an electrolytic cathode at atmospheric pressure. Singular features are revealed of free vapor-air discharges with an electrolytic cathode and their relative transition. Analysis and generalization of the experimental results enable one to reveal the basic physical processes which define the possible mechanism of maintaining a vapor-air discharge with an electrolytic cathode.Translated from Teplofizika Vysokikh Temperatur, Vol. 43, No. 1, 2005, pp. 005–010. Original Russian Text Copyright © 2005 by A. F. Gaisin and E. E. Son.     

Model of glow discharge between an electrolytic anode and a metal cathode

High Temperature - The results of the numerical simulation of the glow discharge between the pin cathode and the electrolytic anode are presented. The electron concentration distribution for the...     

Stable homogeneous microdischarge at atmospheric pressure between a flat cathode and point anode

Conditions of stable operation of a homogeneous glow microdischarge in air at atmospheric pressure between a flat cathode and point anode are established and realized at interelectrode gap widths within ～1–30 μm and discharge currents within from ～10^?4 to 1 A.     

Peculiarities of electric discharge between jet anode and metal cathode

We present the results of a DC electric discharge experimental study between a jet anode and copper cathode at atmospheric pressure. We found the essential influence of the jet anode flow nonuniform character on the discharge development for different power supply regimes. Discharge burning peculiarities are revealed in the jet regime at different power supply voltages with small fluctuation in the milli-, micro-, and nanosecond ranges of the time sweep. We also determined temperatures at the copper cathode surface and its atomization. By means of the Fourier transformation, we reveal the frequency spectrum of the discharge current oscillations.     

Spectral diagnostics of plasma discharge between a metal cathode and liquid anode

The results from studies of an electric discharge between a metal cathode and liquid anode at atmospheric pressure are presented. We investigate the discharge shape, the plasma emission spectrum, the electron concentration and temperature, and the molecule temperature; we analyze the continuous emission in the plasma spectrum and perform infrared thermography.     

Certain features of multichannel discharge in a tube under atmospheric pressure

We present the results of an experimental study of multichannel discharge (MD) in a tube with a pore electrolyte (saturated NaCl solution in industrial water). It is established that the volumetric discharge in the pore electrolyte transfers to the MD. MD development inside long air bubbles is studied. Features of MDs are shown in the case when the discharge fills up the pore electrolyte. It is shown that for fine, ∼2 mm, bubbles, the MD burns around these bubbles.     

Multichannel discharge between jet electrolyte cathode and jet electrolyte anode

We present the results of an experimental study of multichannel discharge between a jet electrolyte cathode and jet electrolyte anode within a wide range of parameters. We pioneer the reveal of the burning particularities and characteristics of multichannel discharge with jet electrolyte and droplet electrodes. The deviations are determined by the voltage and current probability distributions for a multichannel discharge from the normal distribution. We show the dependence of two electrolyte jets merging at the electrical parameters and the character of the jet flow.     

A spherical microwave discharge induced at atmospheric pressure

A discharge induced at the end of an antenna in a flow of argon outgoing into the free space in a coaxial microwave plasmatron is described. Increased energy density supplied to the plasma leads to structuring of the microwave discharge. Effects of the antenna geometry, supplied power, and argon flow rate on the discharge structure are studied.     

Deposition of cathode carbon films in the plasma of a low-current gas discharge at atmospheric pressure

Plasma-chemical deposition of carbon films is carried out under the conditions of an atmospheric-pressure dc discharge from a mixture of hydrocarbons (methane and butane–propane) with helium on substrates (Ni and Cu) that serve as the cathode in the process of discharge. The formation of predominantly disordered films from graphite crystallites is observed at small deposition times. An array of carbon nanotubes coated with structured carbon is formed, as the duration of deposition increases; layers of graphitized scales are formed along the film’s edges.     

Singularities of interaction between a cathode stream and anode vapors in a vacuum arc: Numerical simulation results

Numerical simulation is performed of the process of interaction of cathode and anode ions in a highcurrent vacuum arc with evaporating anode. The presence of the friction force between ion flows, as well as of the friction work, leads to heating and acceleration of slow anode ions and deceleration of fast cathode ions. The boundaries of stable passage of current are determined, associated with the presence of the limiting value of density of anode vapors     

Nonlinear behaviors in a pulsed dielectric barrier discharge at atmospheric pressure

In this paper, the temporal nonlinear behaviors of pulsed dielectric barrier discharge in atmospheric helium are studied numerically by a one-dimensional fluid model. The results show that the common single-period pulsed discharge with two current pulses per single voltage pulse can take place over a broad parameter range. The rising and falling times of the voltage pulse can affect the discharge characteristics greatly. When the discharge is ignited by a pulse voltage with long rising and falling times, a single-period pulsed discharge with multiple current peaks can be observed. Under appropriate rising and falling times of the voltage pulse, a stable period-two discharge can occur over wide frequency and voltage ranges. Also this period-two discharge can exhibit different current and voltage characteristics with changing the duty cycle. With other parameters fixed, the pulsed DBD could be driven to chaos through period-doubling route by increasing either the falling time or the frequency of voltage pulse.     

X-ray emission from a low-current volume discharge in air at atmospheric pressure

The discharges in air gaps with cathodes of small curvature radius under the action of nanosecond high-voltage pulses have been studied. Low-current volume (diffused) discharge in air at atmospheric pressure is a source of x-ray emission. In the case of discharge with a low-intensity visible glow, x-ray emission takes place both from the gap and from the anode surface.