Влияние предыонизации на микроканальную структуру искрового разряда в воздухе в промежутке острие-плоскость

The initial phase of a spark discharge in the gap between the pin (cathode) and a plane 1.5 mm long in atmospheric pressure air under conditions of preliminary photoionization by an auxiliary discharge was investigated by the method of shadow photography. In the absence of preionization, the discharge from the first nanoseconds after breakdown is an aggregate of a large number of micron-diameter channels. It was found that the electron concentration resulting from preionization, estimated at 108  109 cm-3, increases the degree of uniformity of the discharge channel in the near-cathode region; however, in the near-anode region, the channel remains microstructured. Within the framework of the mechanism of microstructure formation due to the instability of the ionization wave front, a criterion for the formation of a uniform discharge is obtained and an explanation of the results obtained is presented.

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Формирование микроканальной структуры искрового разряда в воздухе в промежутке острие-плоскость"

Журнал технической физики ◽

10.21883/jtf.2022.03.52130.235-21 ◽

2022 ◽

Vol 92 (3) ◽

pp. 348

Author(s):

А.А. Тренькин ◽

К.И. Алмазова ◽

А.Н. Белоногов ◽

В.В. Боровков ◽

Е.В. Горелов ◽

...

Keyword(s):

Experimental Data ◽

Formation Mechanism ◽

Atmospheric Pressure ◽

Cathode Region ◽

Spark Discharge ◽

Ionization Wave ◽

Time Interval ◽

Microstructure Formation ◽

Front Instability ◽

Cathode Plane

The formation of the microchannel structure of a spark discharge in the gap spike (cathode)-plane of 1.5 mm length in the air of atmospheric pressure was studied by the method of shadow photography. The images with the concurrent descent of microchannel diameter sand the number of microchannel increase in the cathode region on the time interval of 5 ns were recorded. The obtained data are explained in the frames of the microstructure formation mechanism at the expense of the front instability of the ionization wave. The parameters characterizing the process of the microstructure formation are estimated, and they agree with the experimental data.

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Плазменные и газодинамические приэлектродные процессы в начальной фазе микроструктурированного искрового разряда в воздухе

Письма в журнал технической физики ◽

10.21883/pjtf.2020.15.49740.18336 ◽

2020 ◽

Vol 46 (15) ◽

pp. 10

Author(s):

К.И. Алмазова ◽

А.Н. Белоногов ◽

В.В. Боровков ◽

В.С. Курбанисмаилов ◽

Г.Б. Рагимханов ◽

...

Keyword(s):

Experimental Data ◽

Physical Model ◽

Electron Concentration ◽

Atmospheric Pressure ◽

Initial Phase ◽

Dynamic Parameters ◽

Dynamic Effects ◽

Associated Gas ◽

Electrode Processes ◽

Gas Dynamic

The results of studies of the dynamics of near-electrode processes in the initial phase of the spark are presented. discharge in air at atmospheric pressure in the tip – plane geometry. Near the surface of a flat After the breakdown of the cathode, regions with a size of about 50 μm and more were recorded with an increased electron concentration of (3–8)•10^19 cm^(– 3). Based on experimental data on erosion the effect of a discharge on the surface of a flat electrode and the associated gas-dynamic effects a physical model of near-electrode processes is proposed, based on which estimates are made gas dynamic parameters.

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Electron-concentration measurement in the anode region of a glow discharge at atmospheric pressure in flowing helium

Journal of Applied Spectroscopy ◽

10.1007/bf00662372 ◽

1985 ◽

Vol 43 (5) ◽

pp. 1199-1201

Author(s):

A. I. Golovatyi ◽

S. L. Mazurenko ◽

A. N. Makarevich ◽

D. A. Solov'yanchik

Keyword(s):

Glow Discharge ◽

Electron Concentration ◽

Atmospheric Pressure ◽

Concentration Measurement ◽

Anode Region

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The Influence of Radiation on Arc Constriction in the Anode Region

Journal of Heat Transfer ◽

10.1115/1.3450285 ◽

1975 ◽

Vol 97 (1) ◽

pp. 41-46 ◽

Cited By ~ 7

Author(s):

E. Pfender ◽

J. Schafer

Keyword(s):

Analytical Model ◽

Atmospheric Pressure ◽

High Intensity ◽

Radiation Effects ◽

Relaxation Method ◽

Anode Region ◽

Conservation Equations ◽

Radiation Losses ◽

Argon Arcs

An improved analytical model for the description of the anode contraction zone of a high intensity arc takes radiation effects into account. The conservation equations for the anode contraction zone and the adjacent undisturbed arc column are solved numerically with a relaxation method. Results for atmospheric pressure argon arcs at three different currents demonstrate that radiation losses reduce temperature peaks substantially and, at the same time, provide a smooth matching of arc column and contraction zone solutions. Although the model seems to be adequate for a large portion of the anode contraction zone, the results indicate that refinements of the model are necessary for the region close to the anode, in particular, deviations from LTE have to be taken into account.

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A model of the cathode region of atmospheric pressure arcs

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/28/9/015 ◽

1995 ◽

Vol 28 (9) ◽

pp. 1869-1882 ◽

Cited By ~ 193

Author(s):

M S Benilov ◽

A Marotta

Keyword(s):

Atmospheric Pressure ◽

Cathode Region

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An Investigation of Close-Electrode Intensification in a dc Arc in a Magnetic Field

Applied Spectroscopy ◽

10.1366/000370270774372245 ◽

1970 ◽

Vol 24 (1) ◽

pp. 95-98 ◽

Cited By ~ 1

Author(s):

A. Petrakiev ◽

R. Milanova

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Cathode Region ◽

Spectral Lines ◽

Anode Region ◽

Temperature Range ◽

Dc Arc

An investigation of the distribution of the intensity of spectral lines in the gap length of a copper dc arc of 7A, burning both with and without nonhomogenous magnetic field, will be described in this paper. The close-electrode intensification effect of spectral lines has been observed and its variation with the time of preliminary burning and the gap length has been investigated. It has been established that close-electrode intensification appears only with the ionic lines. An increase of the intensity of some spectral lines and certain variations in their distribution have been observed when the arc is burning in a magnetic field. The temperature range has been studied in its relationship to the gap length. The temperature around the cathode region is approximately 6500 K and that around the anode region is about 6000 K. The superposition of an external magnetic field contributes to an increase of the temperature of about 400 K. Some possibilities for the application of these effects in the case of spectral analytical determinations have been suggested.

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