On the slow ionization waves forming the breakdown in a long capillary tube with helium at low pressure

The results of studies of an electrical breakdown leading to the glow discharge ignition in a long capillary quartz tube are presented. Under such conditions, the breakdown completion is preceded by the development of direct, backward, and counter slow ionization waves traveling in the tube. The initiation of the waves was created in helium at low pressure (P=10 Torr) by the high-voltage pulses of positive and negative polarity with amplitude of several kilovolts. In the beginning, the regime without the breakdown completion in the tube was studied. In this regime, the propagation of only direct positive and direct negative ionization waves happens. The research on dynamics of the direct, backward, and counter positive and negative waves followed by a complete breakdown was done as well. The influence of the pre-existing plasma on the ionization waves propagation was also studied. The plasma was created in advance by low-current glow discharge being formed in the tube. The instant images of ionization waves were correlated with the electrical currents formed by the waves, that is, with the displacement current through the dielectric wall and the conductive current through the plasma column. In the experiments, the fine-sectioned electrode wrapped around the lateral tube surface was used. The usage of such electrode allowed one to study the dynamics of the surface charge deposition and deletion happening during the direct and backward wave propagation, respectively. Finally, a strong difference in the spatial structure and velocity of positive and negative direct waves traveling through non-ionized gas was revealed. Contrary, both the positive and negative backward waves traveling through the plasma formed by previous direct waves have the parameters close to each other.

Hole size effect on microhollow cathode discharge in air

In this work the values of main electrical parameters of the microhollow cathode discharge in atmospheric air (peak discharge current, discharge ignition voltage) depending on the diameter of the hole in the cathode were obtained. It was experimentally found that at currents up to 2 mA, the discharge operated in a self-pulsing mode. According to the experimental results it was concluded that the value of the discharge ignition voltage at average discharge current exceeding 2 mA didn’t depend on the hole diameter.

Features of glow discharge ignition through a small hole in the hollow cathode of a large volume

The influence of the size of a cathode gap on the initiation of the effect of a hollow cathode in a glow discharge system with an extended hollow cathode in the forevacuum pressure range is shown. It was found that the threshold current for the transition of the discharge to the burning mode with a hollow cathode is determined by the ratio of the longitudinal and transverse dimensions of the cathode slit. With a decrease in the width of the slot, the threshold current increases disproportionately; at the same time, with an increase in the length of the slot, this current sharply decreases.

Plasma-electrolyte discharges in a gas-liquid medium for the production of hydrogen

THE PURPOSE. Comprehensive study of the effect of direct current electric discharge plasma in a gas-liquid medium of inorganic mixtures in order to obtain gaseous hydrogen. Obtain volt-ampere, volt-second and ampere-second characteristics of the discharge at various concentrations of electrolyte. Study the process of electrolysis, breakdown, discharge ignition and discharge flow in a dielectric tube at a constant current. METHODS. To solve this problem, experimental studies were carried out on a model installation, which consists of a power supply system, a discharge chamber, equipment for monitoring and controlling the operation of the installation and measuring the characteristics of an electric discharge. To analyze the stability of the discharge, the time dependences of the voltage ripple and the discharge current were obtained. RESULTS. Experimental studies were carried out between the electrolytic cathode and the electrolytic anode at constant current and at atmospheric pressure with the following parameters: discharge voltage U = 0.1-1.5 kV, discharge current I = 0.02-2.3 A, interelectrode distance l = 100 mm , 1%, 3% and 5% solutions of sodium chloride in tap water were used as electrolytes. CONCLUSION. It is shown that electrical breakdown and ignition of a discharge that is stable in time depends on the conductivity of the gas-liquid medium of the electrolyte. The nature of the current-voltage characteristics depends on the random processes occurring in the gas-liquid medium, which is associated with numerous breakdowns occurring in the gas-liquid medium of the electrolyte, combustion and attenuation of microdischarges, the appearance of bubbles, and the movement of the electrolyte inside the dielectric tube. It is shown that the generation of hydrogen and hydrogen-containing components can occur both at the stage of electrolysis and during discharge combustion. A feature of this method is that electrical discharges in the tube increase the release of hydrogen. In this installation, inorganic and organic liquids of a certain composition and concentration can be used. The results of experimental studies made it possible to develop and create a small-sized installation for producing gaseous hydrogen. Tests have shown that a small-sized plant can be taken as the basis for a industrial plant for the production of hydrogen gas.

The impact of neutralizer-free ignition of a radio frequency ion thruster on the lifetime of the ion optics system

In the initial stage of a radio frequency ion thruster (RIT) ignition, an influx of electrons is required from an external source into the discharge chamber and ionization of the neutral gas propellant. A neutralizer-free method for Townsend breakdown discharge ignition based on Paschen’s law was developed in this study. The feasibility of the ignition method was confirmed by performing thousands of ignition experiments. Metallic Molybdenum (Mo), pyrolytic graphite (PG) and Zr[Formula: see text]Ti[Formula: see text]Cu[Formula: see text]Ni[Formula: see text]Be[Formula: see text]alloy acceleration grids were prepared, and ignition-induced damage on the grids was investigated. A field-emission scanning electron microscope was used to inspect surface damage on the grids after multiple ignitions and to analyze the influence of the ignition method on the lifetime of the ion optical system. Grid materials for space missions that require multiple RIT ignitions (10[Formula: see text] should be high-strength blocks that are resistant to sputtering corrosion and high temperature.

Design of CDI (Capasitive Discharge Ignition) and Motor Spark Plugs Test Kits

The Ignition on a motorcycle is an electrical system that produces sparks in the combustion chamber. If there is a mass of ferromagnetic material moving closer to the sensor, then the pulser will generate an electric current. Greater the electric current it generates. With the working principle of such a pulser, it can be used as a rotation sensor and sent to the ignition coil to produce a higher voltage which will produce sparks at the end of the spark plug electrode. The perfection of the system affects the motor work system. A good CDI condition will make it easier to increase the RPM (Rotations Per Minute) and when the spark plugs are in good condition, the motorbike's performance is getting optimal. There can be a useful tool for analyzing the damage to the CDI and the spark on the spark plug by integrating the electronic system in the motor ignition system. An electronic circuit that connects the motorcycle's ignition system through the output of the pulser circuit signal, which triggers the CDI input instead of the pulse magnet. Because the CDI and motor spark plugs are one of the main components that play an important role in the performance of the combustion motor. So that the electrical system can work without using mechanics and can be used as a tool to be able to analyze CDI damage and motor spark plug performance because CDI and spark plugs are some of the main components that play an important role in combustion motor performance. The result is that the tool can test CDI and motor spark plugs efficiently after which it can conclude the damage and can distinguish the characteristics of the CDI and the motor plugs.