Method of local diagnostics of maxwell's plasma by single langmuir probe

FIELD: physics.

SUBSTANCE: claimed method of local diagnosis of Maxwell's plasma using a single cylindrical Langmuir probe provides an introduction to the gas-discharge space of thin probe holder with a probe at the end in the form of a line of metallic yarn connected via source voltage probe to the metal casing of the gas-discharge device or additional supporting electrode. While steps are being taken to protect the probe circuit from electric pickups and building cleaning surface probe, recording its current-voltage characteristic by changing the probe voltage in both directions from the floating potential and determining the electron energy distribution function, the electron concentration, their temperature, and the plasma potential by processing the probe characteristic by one of the known methods. Then, the ion current density is measured per probe under a floating potential, used later to control the purity of the working gas or the state of the experimental vacuum technique.

EFFECT: expansion of the set of measured parameters of the plasma under investigation by determining the thickness of the probe layer and the ion mass in the case when the electron distribution function with respect to the plasma energies is close to the Maxwell function.

2 cl, 1 dwg

 



 

Same patents:

FIELD: physics.

SUBSTANCE: invention relates to physics of plasma. Proposed solenoid allows creation in space area of LxD of 1.6 m x 0.16 man axially symmetric magnetic field, constant in time, with corrugation interval of 0.43 m, maximum and minimum field magnitudes at solenoid axis of 7.3 and 4 Tl, respectively. Current in solenoid windings is varied to vary trial ratio in the range R = 11.8 m. Solenoid design allows fitting of several identical solenoids to create elongated magnetic field of corrugated configuration, for example, three sections arranged sequentially to induce magnetic field in length about 5 m. Since solenoid is intended for experiments with high-temperature nuclear plasma its design incorporates required protection against heat effects of plasma radiation brought to solenoid superconducting part.

EFFECT: higher reliability.

4 cl, 1 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to plasma hardware. Proposed electrode comprises outer wall, in fact, of cylindrical shape, end wall and ledge. End wall is connected with outer wall distal end to made the support for emitter located, mainly, at its centre. Ledge base is located mainly at end wall centre. Ledge configuration allows its split joint with electrode holder. Note here that said ledge is configured to make at least one channel between ledge and said holder for coolant passage when electrode is connected with said holder. In compliance with some versions, said split joint comprises threaded joint. Note here that thread is cut for split joint with electrode holder threaded cooling tube. In compliance with the other versions, said channel is formed by said thread joint.

EFFECT: longer life.

29 cl, 15 dwg

FIELD: electricity.

SUBSTANCE: invention relates to the field of study of physical properties of substances, in particular to investigation of processes in gas-discharge devices and plasma. between electrodes at fixed distance between them the voltage is supplied; the resulted current melts and evaporates thin wire which is arranged in a free space between electrodes; distance between electrodes is selected so that discharge does not occur spontaneously without wire, and conditions for avalanche breakdown of discharge gap are created between electrodes. The discharge channel is placed in the magnetic field, perpendicular to it, that reduces withdrawal of positive ions from the discharge interval, that is an additional source of heat for evaporation of electrodes.

EFFECT: possibility of ignition of independent arc discharge in open free space.

1 dwg

FIELD: electricity.

SUBSTANCE: pulse neutron generator comprises neutron tube (2), energy storage capacitor (9) and high-voltage transformer with multiple-row secondary winding (5) and interrow insulation protruding outside rows and made at the frame shaped as a hollow ferrite cylinder with metal bottom (4), which are placed coaxially in sealed housing (1) filled with dielectric fluid. At that the bottom is connected to the end of secondary winding of the transformer and the neutron tube target. In parallel with secondary winding of high-voltage transformer there is additional winding (6) wound with the wire of high specific resistance and connected with one end to the metal bottom and with its other end to the beginning of secondary winding.

EFFECT: increase in stability and service life of the generator and decrease in its dimensions.

1 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to multiple nozzle plasma tubular burner-precipitator for production of semis for optical fibres. Flow of medium is fed to the burner including initial glass material and carrier gas to allow burner lengthwise axis perpendicular orientation relative to substrate central axis. First partial flow of first gas or gas mix, in particular, precursor gas is fed from the burner bottom side and substrate via at least one nozzle extending in burner horizontal axis. Second partial precursor gas is fed via extra nozzle so that partial flows are combined nearby substrate. Burner comprises means for feeding of one doping additive with the help of precursor gas.

EFFECT: higher efficiency of silicon dioxide particles precipitation.

22 cl, 2 dwg

FIELD: electricity.

SUBSTANCE: method includes generation of boron ion plasma in pulse high-current magnetron discharge, which parameters are sufficient to implement sputtering of boron target and are as follows: current of 10-50A, voltage of 1-2kV, pulse duration of 10-100 mcs. Initiation of pulse high-current magnetron discharge is made by ignition of permanent low-current magnetron discharge with current up to 50mA, voltage up to 2kV and heating by this discharge of the solid boron target heat-insulated with conductive material up to temperature of 400-500C, when sharp increase of specific conductivity of boron takes place up to values sufficient for stable burning of pulse high-current magnetron discharge.

EFFECT: increased content of boron ions in plasma.

2 cl, 2 dwg

FIELD: machine building.

SUBSTANCE: plasma accelerator cathode as per the first version comprises an ignition electrode made as a cup with outlet holes which embraces an emitter unit, the emitters of the latter are united by a common case and are made as hollow cylindrical bushes with a membrane installed on the working medium outlet side. A hole is provided in the membrane opposite every emitter, the axes of the emitters and the holes in the membrane are matched. The axis of any outlet hole in the ignition electrode base does not match the axis of every hole in the emitter unit membrane. The number of outlet holes in the ignition electrode base can coincide with the number of holes in the membrane. Additionally one outlet hole can be made in the ignition electrode base. Bosses can be provided on the outer end face surface of the emitter unit membrane in the zones located opposite the holes of the ignition electrode. The second invention version implies that the holes for working medium outlet are set on the side surface of the ignition electrode. Herewith the axes of the outlet holes of the ignition electrode can be not crossing the symmetry axis of the ignition electrode. Additionally the outer end face surface of the emitter unit can be protected by a housing. The housing is made from the material with increased resistance to spraying of high-energy particles, for example, from carbon.

EFFECT: longer service life of a cathode due to lower damage to the walls of emitter unit's membrane holes caused by high-energy ions from plasma placed outside the cathode.

7 cl, 3 dwg

FIELD: physics, optics.

SUBSTANCE: invention relates to laser technologies. The method of obtaining of optical discharge in gas consists in optical breakdown of gas with formation of absorbing plasma domain and its maintaining in a laser beam during its action. Meanwhile gas breakdown with formation of plasma domain is performed by focusing of radiation of short-pulse laser, and the maintaining of plasma domain is performed in the resonator of continuous laser or laser with long duration of impulse due to multiple passing of radiation of continuous laser or laser with long duration of impulse through the optical discharge.

EFFECT: enhanced efficiency of laser energy utilisation.

6 cl, 2 dwg

FIELD: electrical engineering.

SUBSTANCE: this device comprises gas discharge chamber composed of two spherical metal electrodes separated by insulator, pulse current generator composed of capacitor bank with HV initiation switch and working gas generator with electric power supply. Besides, it incorporates shunting switch arranged at rear part of electrodes outside the chamber. It is composed of cylindrical discharger with HV electrode and case with spark firing sources arranged thereat. Said switch can be composed of industrial HV semiconductor commutators.

EFFECT: minimised ingress of impurities into discharge chamber, longer life and higher yield of penetrating rays.

3 cl, 1 dwg

FIELD: technological processes.

SUBSTANCE: invention relates to the field of plasma treatment of materials, in particular, for application of coatings, and may find application in plasma metallurgy, plasma chemistry and machine building industry. In a plasmatron comprising a cathode with a cylindrical thermoemission insert, a nozzle-anode, an insulator, a swirling unit with tangential holes, a water cooling system, a channel of simultaneous introduction of a plasma-generating gas and powder, the operation of arc is organised not in the subsonic part, but in supersonic part of the nozzle-anode. At the same time the cylindrical thermoemission insert of the cathode is made in the form of a central body of the nozzle-anode, the summary area of cross sections of tangential holes of the swirling unit is equal to the area of a slot clearance between the wall of the nozzle-anode and the cylindrical thermoemission insert of the cathode, the end of which matches the start of the expanding supersonic part of the nozzle-anode.

EFFECT: increased reliability of operation of a plasmatron in application of coatings from powders of substances with different melting temperature, simplified design of a plasmatron and improved operating and physical and mechanical characteristics of coatings.

2 dwg

FIELD: plasma physics and controlled nuclear fusion problem.

SUBSTANCE: proposed central solenoid used as tokamak inductor and easily dismounted from central column has four conductor layers with inner cooling ducts. Each layer is made separately with four entrances in each layer. All sixteen conductors are connected in series and their junctions are disposed on butt-end surfaces of solenoid switching blocks. Insulated layers of conductors are inserted one into other.

EFFECT: reduced operating loads, enhanced uniformity of magnetic field.

1 cl, 1 dwg

FIELD: spacecraft power systems using solar batteries and electric jet plasma engines, mainly stationary engines.

SUBSTANCE: proposed method includes stabilization and change of power of power plant through regulation of consumption of engine working medium. When power of solar battery drops to level of maximum permissible power consumed by engine, consumption of working medium is changed in such way that power of solar battery might change in saw-tooth pattern and vertices of saw might be in contact with line of maximum probable power of solar battery. Device proposed for realization of this method includes matching voltage converter whose outputs are connected with engine electrodes and inputs are connected with solar battery busbars, current and voltage sensors showing solar battery voltage and power sensor connected with current and voltage sensors. Comparator connected with power sensor is also connected with controllable power setter and initial power setter. Outputs of controllable power setter are connected with comparator and comparison circuit whose input is connected with power sensor output. Output of comparison circuit is connected with amplifier-regulator of consumption of working medium.

EFFECT: enhanced reliability; simplified construction and facilitated procedure of regulation of power.

3 cl, 2 dwg

FIELD: plasma generation.

SUBSTANCE: electrode set of plasma cathode has hollow cylindrical cathode with slit-shaped output aperture and hollow anode. Height of the latter depends on distance between cathode aperture and control grid. Ratio of anode height and control grid transverse incision is greater than unity. Cathode aperture width depends on thickness of spatial charge cathode layer.

EFFECT: enlarged surface area of plasma uniformly emitting electrons.

1 cl, 1 dwg

FIELD: space engineering.

SUBSTANCE: method comprises short-term service life testing, measuring liner sizes of the erosion profiles of the walls of discharging chamber, predicting new erosion profiles, measuring the area of erosion, determining dependence between the measurements of thrust and total area of erosion, and determining proportionality coefficient between the thrust and total erosion area.

EFFECT: enhanced accuracy of predicting.

2 dwg

FIELD: mechanical engineering; low-temperature plasma generation for material treatment at below-atmospheric pressure.

SUBSTANCE: proposed microwave plasmatron has flash chamber whose inner conductive surface bears one or more annual radial slots that can be made in the form of short-circuited lengths of coaxial line with conducting walls, their depth being equal to quarter-wavelength of generator electromagnetic oscillations.

EFFECT: enhanced efficiency of electromagnetic interaction with plasma-forming gas.

1 cl

FIELD: mechanical engineering; low-temperature plasma generation for material treatment at below-atmospheric pressure.

SUBSTANCE: proposed microwave plasmatron has flash chamber whose inner conductive surface bears one or more annual radial slots that can be made in the form of short-circuited lengths of coaxial line with conducting walls, their depth being equal to quarter-wavelength of generator electromagnetic oscillations.

EFFECT: enhanced efficiency of electromagnetic interaction with plasma-forming gas.

1 cl

FIELD: mechanical engineering; low-temperature plasma generation for material treatment at below-atmospheric pressure.

SUBSTANCE: proposed microwave plasmatron has flash chamber whose inner conductive surface bears one or more annual radial slots that can be made in the form of short-circuited lengths of coaxial line with conducting walls, their depth being equal to quarter-wavelength of generator electromagnetic oscillations.

EFFECT: enhanced efficiency of electromagnetic interaction with plasma-forming gas.

1 cl

FIELD: production of nanodispersed powders of refractory inorganic materials and compounds, in particular, installations and methods for realization of plasmochemical processes of production of nanodispersed powder products.

SUBSTANCE: the installation comprises production-linked: microwave oscillator 1, microwave plasmatron 2, gas-flow former 3, discharge chamber 4, microwave radiation absorber 5, reaction chamber 6, heat-exchanger 7, filter-collector of target product (powder) 8, device for injection of the source reagents in a powdered or vapors state into the reaction chamber, the installation has in addition a device for injection of the source reagents in the liquid-drop state, it has interconnected proportioner 9 in the form of cylinder 10, piston 11 with gear-screwed electric drive mechanism 12 adjusting the speed of motion of piston 1, evaporative chamber 13 with a temperature-controlled body for regulating the temperature inside the chamber that is coupled to the assembly of injection of reagents 14 in the vaporous state and to the assembly of injection of reagents 15 in the liquid-drop state, injection assembly 14 is made with 6 to 12 holes opening in the space of the reaction chamber at an angle of 45 to 60 deg to the axis of the chamber consisting at least of two sections, the first of which is connected by upper flange 16 to the assemblies of injection of reagents, to discharge chamber 4, plasmatron 2, with valve 17 installed between it and microwave oscillator 1, and by lower flange 18, through the subsequent sections, it is connected to heat exchanger 7, the reaction chamber has inner water-cooled insert 20 rotated by electric motor 19 and metal scraper 21 located along it for cutting the precipitations of powder of the target product formed on the walls of the reaction chamber, and heat exchanger 7 is made two water-cooled coaxial cylinders 22 and 23, whose axes are perpendicular to the axis of the reaction chamber and installed with a clearance for passage of the cooled flow, and knife 24 located in the clearance, rotating about the axis of the cylinders and cleaning the working surfaces of the cylinders of the overgrowing with powder, powder filter-collector 8 having inside it filtering hose 25 of chemically and thermally stable material, on which precipitation of powder of the target product from the gas flow takes place, in the upper part it is connected by flange 26 to the heat exchanger, and in the lower part the filter is provided it device 27 for periodic cleaning of the material by its deformation, and device 28 with valve 29 for sealing the inner space of the filter. The method for production of nanodispersed powders in microwave plasma with the use of the claimed installation consists in injection of the source reagents in the flow of plasma-forming gas of the reaction chamber, plasmochemical synthesis of reagents, cooling of the target product and its separation from the reaction chamber through the filter-collector, the source reagents are injected into the flow of plasma-forming gas, having a medium-mass temperature of 1200 to 3200 K in any state of aggregation: vaporous, powdered, liquid-drop or in any combination of them, reagents in the powdered state are injected in the form of aerosol with the gas-carrier into the reaction chamber through injection assembly 35 with a hole opening into the space of the reaction chamber at an angle of 45 to 60 deg to the chamber axis, reagents in the liquid-drop or vaporous state are injected into the reaction chamber through injection assemblies 15 or 14, respectively, in the form of ring-shaped headers, the last of which is made with 6 to 12 holes opening into the space of the reaction chamber at an angle of 45 to 60 deg to the chamber axis, each of them is blown off by the accompanying gas flow through the coaxial ducts around the holes, at expenditure of the source reagents, plasma-forming gas, specific power of microwave radiation, length of the reaction zone providing for production of a composite system and individual substances with preset properties, chemical, phase composition and dispersity.

EFFECT: universality of the industrial installation, enhanced capacity of it and enhanced duration of continuous operation, as well as enhanced yield of nanodispersed powders and expanded production potentialities of the method.

20 cl, 1 dwg, 4 ex

FIELD: high-energy ultraviolet and roentgen radiation sources.

SUBSTANCE: high-energy photon source has electrode pair 8 for producing plasma pinch disposed in vacuum chamber of plasma pinch generating device 2. Chamber holds working gas incorporating noble cushion gas and active gas chosen to afford generation of desired spectral line. Switching-mode power supply 10 generates electric pulses of sufficiently high voltage to build up electrical discharge between electrodes. This discharge produces high-temperature plasma pinches of high density in working gas which generate radiation in spectral line of power supply. Electrodes are of coaxial configuration with anode on axis. Active gas is introduced through hollow anode.

EFFECT: ability of optimizing spectral line of source and optimizing the latter separately with respect to cushion gas.

22 cl, 17 dwg

FIELD: plasma technologies.

SUBSTANCE: device has two electrodes, dielectric blocks, made of special material, discharge channel with open end portion, walls of which are formed by surfaces of electrodes and dielectric blocks, energy accumulator, current feeds, connecting electrodes to energy accumulator, which together with electrodes and accumulator form an external electric circuit, isolator, mounted between electrodes near end portion of discharge channel, opposite to open end portion, and charge initiation device. Characteristics of external electrical circuit of accelerator are selected from condition : 2≤C/L, where C - electric capacity of external electric circuit in micro-farads, and L - inductiveness of external electric circuit in nh, value of which satisfies the condition: L≤100 nh. Plasma acceleration method includes ignition of charge in discharge channel of plasma accelerator in pulse feed of discharge voltage from energy accumulator to electrodes of plasma accelerator. In discharge channel of accelerator quasi-periodic pulse discharges are ignited and maintained with value of discharge voltage U no less than 1000 volts and above-mentioned characteristics of accelerator electric circuit.

EFFECT: higher efficiency.

2 cl, 9 dwg

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