EP0032100B1 - Vorrichtung zum Erzeugen von ionisiertem Gas mit hohem Druck und sehr hoher Temperatur - Google Patents

Vorrichtung zum Erzeugen von ionisiertem Gas mit hohem Druck und sehr hoher Temperatur Download PDF

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Publication number
EP0032100B1
EP0032100B1 EP80401878A EP80401878A EP0032100B1 EP 0032100 B1 EP0032100 B1 EP 0032100B1 EP 80401878 A EP80401878 A EP 80401878A EP 80401878 A EP80401878 A EP 80401878A EP 0032100 B1 EP0032100 B1 EP 0032100B1
Authority
EP
European Patent Office
Prior art keywords
electrode
gas
ionized gas
modules
electrodes
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP80401878A
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English (en)
French (fr)
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EP0032100A2 (de
EP0032100A3 (en
Inventor
Serge Denoyer
Jacques Guerin
Maxime Labrot
Jean-Pierre Serrano
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
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Publication of EP0032100A2 publication Critical patent/EP0032100A2/de
Publication of EP0032100A3 publication Critical patent/EP0032100A3/fr
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Publication of EP0032100B1 publication Critical patent/EP0032100B1/de
Expired legal-status Critical Current

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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/48—Generating plasma using an arc
    • H05H1/50—Generating plasma using an arc and using applied magnetic fields, e.g. for focusing or rotating the arc
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/26—Plasma torches
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/26—Plasma torches
    • H05H1/32—Plasma torches using an arc
    • H05H1/44—Plasma torches using an arc using more than one torch

Definitions

  • the present invention relates to the production of ionized gas at very high temperature and very high pressure, by heating by means of electric arcs of high power in direct current. It is known, in particular in space techniques, to effectively use such ionized gas generators to test and choose thermal protection materials for space vehicles whose trajectories include in particular a rapid re-entry phase into the atmosphere, during which the external component parts of the vehicle are brought very quickly to temperatures of several thousand degrees.
  • the two families of generators are used to test the test pieces as follows.
  • test pieces of material introduced or previously positioned in the flow, are subjected to aerothermal conditions similar to those which will be undergone by the same material equipping the spacecraft during the atmospheric reentry phase.
  • the test pieces of material introduced into the axis of the jet are generally of sphero-conical or sphero-cylindrical shape (so-called "breakpoint” tests).
  • the test pieces of material previously positioned parallel to the axis of the jet are of parallelepiped shape (so-called "square tube” tests).
  • test specimens in the jet axis are subjected to more severe aerothermal conditions than those parallel to the jet axis, but with measurement results that are more difficult to use.
  • Generators of the second family have the major drawback of low performance in generating pressure, prohibiting all a range of tests with test pieces placed in a configuration of the "breakpoint" type.
  • the present invention specifically relates to an ionized gas generator for the study of test specimens at very high temperature and very high pressure which makes it possible to combine the advantages specific to each of the two families of preceding generators, by allowing the production of ionized gas at very high generating pressures and moderate enthalpies with a flow of homogeneous ionized gas and without direct radiation of the arc on the test piece of material to be tested.
  • the means for injecting the gas in vortices into each module consist of a pressurized gas supply chamber associated with a gas injection ring consisting of a part cylindrical metal pierced with orifices opening tangentially to the internal wall of the crown and distributed uniformly over this wall in the injection space between the upstream electrode and the downstream electrode.
  • the unit modules are four in number
  • the coupling chamber consists of a central part provided with a spherical recess which are connected by centered way five cylindrical passages, namely the first four located in the same plane at 90 ° from each other, and in each of which opens the jet of ionized gas from one of the modules, and a fifth, perpendicular to the plane of the first four , and which carries the emission nozzle of the ionized gas jet from the generator.
  • the generator 1 consisting of a support 10 in four parts of cruciform arrangement.
  • the generator itself consists of four modules 11, 12, 13 and 14 located all four in the vertical plane containing the axes XY and X'Y '; the modules are aligned two by two, namely on the one hand the modules 11 and 13 which are vertical, and on the other hand the modules 12 and 14 which are horizontal.
  • the previous four modules 11, 12, 13 and 14 are associated with a coupling chamber 15 also located in the plane of FIG. 1, and from which emerges, perpendicular to this same plane, a nozzle 16 gathering the overall gas flow ionized generated by the four generator modules.
  • the gas heated and ionized by an electric arc produced in each module is collected at the level of the coupling chamber 15, then expanded through the nozzle 16 so as to produce a homogeneous and supersonic flow at very high temperature and at high speed, flow perpendicular to the vertical plane of Figure 1 which includes the axes of the four modules.
  • FIG. 2 shows the casing 20 of the upstream electrode 22 and the casing 21 of the downstream electrode 23.
  • these two electrodes are substantially cylindrical and arranged in the same alignment along their common axis 24
  • the electrode 23 is pierced right through, which allows, as will be seen below, the injected gas to flow from one end to the other thereof.
  • a chamber 25 separates the two upstream 22 and downstream 23 electrodes, a chamber into which the generator supply gas is injected, as will be seen below.
  • a direct current electric arc 26 is struck in the space 25 between the end of the electrode 22 and the electrode 23 using an auxiliary starting electrode 27 which can in particular be of any known type. Under the action of the air injected into the chamber 25, and which flows towards the outlet of the hollow cylindrical electrode 23, the electric arc also expands and takes a very elongated shape characteristic of the generator object of the present invention.
  • the injection of gas into the chamber 25 is carried out as follows.
  • the gas is injected, by any known system, at 17 into a supply chamber 28, which communicates with a gas injection ring 30 consisting of a metallic cylindrical piece pierced with orifices opening tangentially to the internal wall of the crown and distributed uniformly on this wall in the injection space 25 between the upstream electrode 22 and the downstream electrode 23.
  • the injection holes in the crown are distributed in four planes 31, 32, 33 and 34 equidistant from each other and perpendicular to the common axis of the device 24.
  • a cooling circuit 35 supplied by the input 36 is located around the upstream electrode 22 between this electrode proper and its envelope 20.
  • the cooling liquid circulating in these envelopes allows the electrodes to be cooled vigorously. during operation of the device.
  • An identical structure also equips the downstream electrode 23 which is surrounded by a cooling circuit 38 supplied by the inlet 37 located in the electrode casing 21.
  • the gas injection ring 30 is provided with its own inlet 40 and outlet 41 water cooling circuit in FIG. 2 and consisting of a number of bores parallel to the common axis 24 of the generator and distributed over the circumference of the crown gas injection 30.
  • the gas injection ring is, by construction, at the same potential as the downstream electrode 23. It was therefore necessary to provide a device for electrical and thermal isolation of this ring d injection 30 relative to the upstream electrode 22.
  • This double thermal and electrical insulation consists of a nylon sheath 42 which provides electrical insulation and a ring of silicon nitride 43 which provides thermal insulation.
  • the module of FIG. 2 is connected to the coupling chamber 15 by a connecting piece 46.
  • the coupling chamber 15 itself is constituted by an external casing 50 of copper or copper alloy, of cubic shape, in which is located an internal piece 51 in one piece and also made of copper or copper alloy comprising a spherical recess 51 a and five cylindrical passages 51 b connecting to the spherical recess 51 a.
  • the first four of these cylindrical passages 51b are in direct communication with the downstream electrodes 23 of each module and the fifth opens directly onto the nozzle 16, as can be seen in FIG. 3. Also shown in dotted lines in FIG. 2 , the path of the cooling circuit 55 of the internal part 51 and of the cooling circuit 62 of the nozzle 16.
  • the coupling chamber proper is constituted by an external block 50 of cubic shape and in which is hollowed a cavity coated with an internal part 51 of red copper or copper alloy, monobloc, comprising a spherical recess 51 connected to five cylindrical passages 51 b of which only three are of course visible in FIG.
  • FIG. 3 also shows the electrode 22 of the module 12 as well as the electrode 22b of the module 14 also provided with their respective cooling circuits 38 and 39.
  • the generator which has just been described operates in the following manner: the various cooling circuits such as 38, 39, 41, 57, 58, 59 and 60 are initially supplied from a network of pumps and valves allowing the individual control of these circuits in pressures and flows, at values such that the differences between these pressures and the atmospheric pressure initially prevailing in the generator are small.
  • the coils 44 producing the magnetic field are energized.
  • a short circuit is then produced between the upstream electrode 22 and the end piece of the central rod of the starting electrode 27.
  • the gas is then injected into the generator through the orifices located in the planes 31, 32, 33 and 34 with regard to the module shown in FIG.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Plasma Technology (AREA)
  • Electron Sources, Ion Sources (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)

Claims (3)

1. Vorrichtung zum Erzeugen von ionisiertem Gas mit homogener Überschallströmung von der Art, welche umfaßt: eine Vielzahl von Einheitsmodulen (11, 12, 13, 14), die koplanare Achsen aufweisen und mit einer Kopplungskammer (15) verbunden sind, die eine zu der die Achsen der Module enthaltenden Ebene senkrechte Düse (16) aufweist, wobei die Modulen zwei mit Hochspannung von wenigstens mehreren 1000 Volt versorgte Elektroden (22, 23) aufweisen, die koaxial, von im wesentlichen hohlzylindrischer Form und hintereinander angeordnet sind, wobei eine (22) stromaufwärts und die andere (23) stromabwärts bezüglich der Strömungsrichtung des ionisierten Gases angeordnet ist und die stromaufwärtige Elektrode (23) offen ist und von dieser Strömung durchquert wird, dadurch gekennzeichnet, daß ferner in jedem Einheitsmodul vorgesehen sind:
- Mittel (30), um ein Gas wirbelförmig längs der Ebenen, die senkrecht zu der gemeinsamen Achse der Elektroden verlaufen, in den Zwischenbereich zwischen der stromaufwärtigen Elektrode (22) und der stromabwärtigen Elektrode (23) einzublasen, wobei das derart eingeblasene Gas einen Lichtbogen (26) durchquert, der dadurch eine längliche Form annimmt, welche sich von der stromaufwärtigen Elektrode (22) bis zum Ende der stromabwärtigen Elektrode (23) erstrecken kann, die an ihrem Ende offen ist und in eine der Eintrittsöffnungen der Kopplungskammer (15) mündet,
- Mittel (27) zum Zünden des Bogens zwischen den zwei koaxialen Elektroden (22, 23),
- Mittel (35) zum Kühlen der Elektroden, Einrichtungen zum Einblasen von Gas (30) und die Kopplungskammer (15), und
- Spulen (44), die um die erste stromaufwärtige Elektrode (22) ein Magnetfeld erzeugen, welches ein Verschieben des Fußes des Bogens (26) an der Innenfläche der stromaufwärtigen Elektrode (22) herum sicherstellt, und daß die Elektroden (22, 23) außerdem aus Kupfer oder einer Kupferlegierung bestehen.
2. Vorrichtung zum Erzeugen von ionisiertem Gas nach Anspruch 1, dadurch gekennzeichnet, daß die Mittel zum Einblasen von Gas in Wirbelform in jedes Modul (11, 12, 13, 14) aus einer Kammer (28) zur Versorgung mit Druckluft bestehen, die mit einer Lufteinblaskrone (30) verbunden ist, welche von einem zylinderförmigen Metallteil gebildet ist, durch welches Öffnungen gebohrt sind, die tangential an der Innenwandung der Krone (30) münden und gleichförmig über diese Innenwandung im Einblasraum (25) verteilt sind, der von der stromaufwärtigen Elektrode (22) und der stromabwärtigen Elektrode (23) umfaßt wird.
3. Vorrichtung zum Erzeugen von ionisiertem Gas nach einem der Ansprüche 1 oder 2, dadurch gekennzeichnet, daß die Anzahl der Einheitsmodulen (11, 12, 13, 14) vier beträgt und daß die Kopplungskammer (15) aus einem inneren Teil (51) besteht, welches eine kugelförmige Ausmuldung (51a) aufweist, an die in zentrierter Weise fünf zylinderförmige Durchgänge (51 b) anschließen, d. h. vier erste, die in der gleichen Ebene und mit 90° aufeinanderfolgend angeordnet sind und in die jeweils der ionisierte Gasstrahl von einem der Modulen mündet und ein fünfter, zur Ebene der vier ersten senkrechter Durchgang, der die Austrittsdüse (16) des ionisierten Gasstrahls der Vorrichtung trägt.
EP80401878A 1980-01-07 1980-12-29 Vorrichtung zum Erzeugen von ionisiertem Gas mit hohem Druck und sehr hoher Temperatur Expired EP0032100B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8000231 1980-01-07
FR8000231A FR2473248A1 (fr) 1980-01-07 1980-01-07 Generateur de gaz ionise a tres haute pression et tres haute temperature

Publications (3)

Publication Number Publication Date
EP0032100A2 EP0032100A2 (de) 1981-07-15
EP0032100A3 EP0032100A3 (en) 1981-08-05
EP0032100B1 true EP0032100B1 (de) 1984-03-14

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EP80401878A Expired EP0032100B1 (de) 1980-01-07 1980-12-29 Vorrichtung zum Erzeugen von ionisiertem Gas mit hohem Druck und sehr hoher Temperatur

Country Status (7)

Country Link
US (1) US4426597A (de)
EP (1) EP0032100B1 (de)
JP (1) JPS56107452A (de)
AU (1) AU537026B2 (de)
CA (1) CA1167114A (de)
DE (1) DE3067071D1 (de)
FR (1) FR2473248A1 (de)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4549065A (en) * 1983-01-21 1985-10-22 Technology Application Services Corporation Plasma generator and method
US4707583A (en) * 1983-09-19 1987-11-17 Kennecott Corporation Plasma heated sintering furnace
US4559312A (en) * 1983-09-19 1985-12-17 Kennecott Corporation Sintering or reaction sintering process for ceramic or refractory materials using plasma arc gases
JPH0763033B2 (ja) * 1984-06-27 1995-07-05 吉明 荒田 大出力プラズマジェット発生装置
US4625092A (en) * 1984-11-30 1986-11-25 Plasma Energy Corporation Plasma arc bulk air heating apparatus
US4649002A (en) * 1985-04-01 1987-03-10 Kennecott Corporation System for preventing decomposition of silicon carbide articles during sintering
US4666775A (en) * 1985-04-01 1987-05-19 Kennecott Corporation Process for sintering extruded powder shapes
US4676940A (en) * 1985-04-01 1987-06-30 Kennecott Corporation Plasma arc sintering of silicon carbide
US4698481A (en) * 1985-04-01 1987-10-06 Kennecott Corporation Method for preventing decomposition of silicon carbide articles during high temperature plasma furnace sintering
FR2614750B1 (fr) * 1987-04-29 1991-10-04 Aerospatiale Electrode tubulaire pour torche a plasma et torche a plasma pourvue de telles electrodes
US4931700A (en) * 1988-09-02 1990-06-05 Reed Jay L Electron beam gun
FR2654295B1 (fr) * 1989-11-08 1992-02-14 Aerospatiale Torche a plasma pourvue d'une bobine electromagnetique de rotation de pieds d'arc.
US5079482A (en) * 1991-02-25 1992-01-07 Villecco Roger A Directed electric discharge generator
US5686050A (en) * 1992-10-09 1997-11-11 The University Of Tennessee Research Corporation Method and apparatus for the electrostatic charging of a web or film
US5955174A (en) * 1995-03-28 1999-09-21 The University Of Tennessee Research Corporation Composite of pleated and nonwoven webs
WO1997013266A2 (en) 1995-06-19 1997-04-10 The University Of Tennessee Research Corporation Discharge methods and electrodes for generating plasmas at one atmosphere of pressure, and materials treated therewith
CN100383514C (zh) * 2005-07-20 2008-04-23 哈尔滨工业大学 防热材料地面模拟试验装置控制与监测系统
AU2019205004B1 (en) * 2019-07-11 2020-10-01 Iyinomen, Daniel Odion DR A Novel Plasma Preheating Test Device for Replicating Planetary Reentry Surface Temperatures in Hypersonic Impulse Facilities

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3543084A (en) * 1968-01-22 1970-11-24 Ppg Industries Inc Plasma arc gas heater

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3543083A (en) * 1967-09-15 1970-11-24 Bendix Corp Method and means for providing a display of moving bands of light
US4105888A (en) * 1976-07-09 1978-08-08 Westinghouse Electric Corp. Arc heater apparatus for producing acetylene from heavy hydrocarbons

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3543084A (en) * 1968-01-22 1970-11-24 Ppg Industries Inc Plasma arc gas heater

Also Published As

Publication number Publication date
FR2473248B1 (de) 1983-09-30
EP0032100A2 (de) 1981-07-15
CA1167114A (en) 1984-05-08
AU537026B2 (en) 1984-05-31
FR2473248A1 (fr) 1981-07-10
AU6596281A (en) 1981-07-16
JPH0159695B2 (de) 1989-12-19
US4426597A (en) 1984-01-17
DE3067071D1 (en) 1984-04-19
EP0032100A3 (en) 1981-08-05
JPS56107452A (en) 1981-08-26

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