EP0871957A2 - Source electrostatique de neutrons/protons obtenus par fusion et soumis a une acceleration/circulation - Google Patents

Source electrostatique de neutrons/protons obtenus par fusion et soumis a une acceleration/circulation

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Publication number
EP0871957A2
EP0871957A2 EP96922455A EP96922455A EP0871957A2 EP 0871957 A2 EP0871957 A2 EP 0871957A2 EP 96922455 A EP96922455 A EP 96922455A EP 96922455 A EP96922455 A EP 96922455A EP 0871957 A2 EP0871957 A2 EP 0871957A2
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EP
European Patent Office
Prior art keywords
neutron
vacuum chamber
proton source
magnetic field
cathode
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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.)
Withdrawn
Application number
EP96922455A
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German (de)
English (en)
Other versions
EP0871957A4 (fr
Inventor
George Miley
Yibin Gu
Jalai B. Javedani
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Individual
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Individual
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Application filed by Individual filed Critical Individual
Publication of EP0871957A2 publication Critical patent/EP0871957A2/fr
Publication of EP0871957A4 publication Critical patent/EP0871957A4/en
Withdrawn legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21B—FUSION REACTORS
    • G21B1/00—Thermonuclear fusion reactors
    • G21B1/05—Thermonuclear fusion reactors with magnetic or electric plasma confinement
    • 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
    • H05H3/00—Production or acceleration of neutral particle beams, e.g. molecular or atomic beams
    • H05H3/06—Generating neutron beams
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/10—Nuclear fusion reactors

Definitions

  • This invention relates to a particle generator and, more particularly, to an electrostatic accelerated-recirculating fusion neutron/proton source ("neutron/proton source”) that confines controlled nuclear fusion reactions inside a negative potential well structure.
  • neutral/proton source electrostatic accelerated-recirculating fusion neutron/proton source
  • IEC inertial-electrostatic confinement
  • U.S. Patent 3,386,883 issued to P.T. Farnsworth discloses ion guns mounted around a spherical anode that surrounds a spherical cathode. Ions from the guns are focused into the center ofthe cathode.
  • U.S. Patent 3,258,402 also issued to P.T. Farnsworth is an earlier version ofthe same device that discloses a spherical cathode surrounding a spherical anode. This patent suggests that with a proper choice of materials for the cathode, the central gas may be ionized by electron emission from the cathode, thus eliminating the need for ion guns.
  • U.S. Patent 3,530,497 issued to Hirsch et al. also illustrates a spherical anode, a concentrically positioned ion-source grid, and a cathode, which is spherical and is permeable to charged particle flow.
  • both the spherical cathode and the ion-source grid are required and the ion-source grid is placed between the cathode and the anode.
  • Varying potentials are applied to each ofthe three electrodes, thus establishing a first electric field in the space between the anode and the ion-source grid, and a second electric field in the space between the ion-source grid and the cathode, which is at a different potential than the first electric field.
  • Ions formed inside the ion-source grid are propelled toward the centrally located cathode due to the potential difference. These ions are focused toward the center of the inside ofthe cathode where they interact, thereby producing a fusion reaction.
  • This device requires an ion-source grid in addition to the spherical cathode and anode. Furthermore, a thermionic cathode is required in the space between the outer anode and the ion-source grid, such that electrons from the thermionic cathode will flow toward the grid rather than to the outer anode. With the addition of each element, the complexity and cost ofthe apparatus increases.
  • IEC devices Problems with the prior art IEC devices include that they are expensive to manufacture, are bulky, and require precise alignment of components, such as ion guns, in order to operate properly. With these complications, their use was intended for higher- intensity applications, viewed as leading to a fusion energy source, which implies neutron emission rates above 10 14 neutrons per second ("n/s"). Other applications, such as neutron activation analysis, require a compact lower-intensity source (i.e. about 10° n/s), which is typically met using radioisotope neutron sources, e.g. Cf-252. However, disadvantages of such radioisotopes include their relatively short half lives and the broad energy spectrum of their emitted neutrons.
  • radioisotope design does not have an on/off capability.
  • the source must be stored in bulky protective shielding when not in use.
  • Cf-252 must be produced using a high-flux fission reactor, making it expensive and, due to a reduction in such reactors operating in the U.S. in recent years, fairly scarce.
  • Another alternate low-intensity neutron source uses a miniature deuteron accelerator to bombard a solid target coated with tritium.
  • R.C. Smith, et al., IEEE Trans, on Nuc. Sci.. 3_5_, 1, 859 [1988] Currently available small (i.e. 10 6 - 10 8 n/s) neutron generators of this type use a titanium target coated with deuterium or a deuterium-tritium mixture.
  • the device typically operates in a short-pulse mode with a moderate repetition rate in order to avoid overheating ofthe target. Versions of this concept with higher neutron intensities have been built using a high-speed rotating target to prevent overheating, but these devices are very expensive.
  • the present invention is intended to overcome the disadvantages of these various low- intensity neutron/proton sources.
  • an electrostatic accelerated-recirculating fusion neutron/proton source comprising and axially elongated hollow vacuum chamber having an inner and outer wall. Reflectors are located at opposite ends ofthe vacuum chamber so that their centers lie on the axis ofthe vacuum chamber.
  • a cathode that is 100% transparent to oscillating particles is located within the vacuum chamber between the reflectors, defining a central volume and having the same axis as the vacuum chamber.
  • Anodes that are 100% transparent to oscillating particles are located near opposite ends ofthe vacuum chamber between the reflectors and the cathode, having axes coincident with the axis ofthe vacuum chamber.
  • a means is also provided for introducing controlled amounts of reactive gas into the vacuum chamber, and its central volume.
  • a means is provided for applying an electric potential between said anodes and said cathode and said reflectors dishes to produce ions from the reactive gas within the central volume and to cause the recirculation of ions and electrons within the vacuum chamber, thus reducing the loss of particles.
  • a means for generating a magnetic field in the axial direction is attached to the circumference ofthe vacuum chamber.
  • Another object is to provide a neutron/proton source with a cathode that is 100% transparent to oscillating ions, thereby allowing high ion recirculation and eliminating ion- cathode collisions, which reduces ion losses and overheating and erosion ofthe cathode.
  • Another object is to provide a neutron/proton source that is simple in its operation and construction, sturdy in its design and is a low-cost fusion neutron/proton source.
  • Another object is to provide a neutron/proton source that is easily portable.
  • Another object is to provide a neutron/proton source that does not use a radioisotope neutron source.
  • Another object is to provide a neutron/proton source with two anodes and two reflectors that create positive potential wells, which allow electrons to oscillate within the potential wells, thereby reducing ion loss rate.
  • Another object is to provide a neutron/proton source with two anodes that are 100% transparent to oscillating particles, thereby allowing high particle recirculation and eliminating particle-anode collisions, which reduces particle losses and overheating and erosion ofthe anodes.
  • Another object ofthe invention is to provide a neutron/proton source with good recirculatory ion beam focusing due to an electron microchannelling effect caused by hollow cylindrical anodes.
  • Another object ofthe invention is to provide a neutron proton source that produces a plurality of dense ion beams, thereby causing a greater number of particle collisions.
  • Still another object ofthe invention is to provide a neutron/proton source with a magnetic field that confines particles in the radial direction, thereby reducing further the particle loss rate.
  • Fig. 1 is a diagrammatic illustration ofthe neutron/proton source embodying the present invention.
  • Fig. 2 is a diagram ofthe idealized negative and positive electric potential wells generated by the cylindrical cathode, cylindrical anodes and reflecting dishes.
  • Fig. 3 is a diagrammatic illustration of an alternate embodiment ofthe neutron/proton source having a plurality of magnetic rings.
  • the portable electrostatic accelerated-recirculating fusion neutron/proton source 10 ofthe present invention first comprises a hollow vacuum chamber 20.
  • the hollow vacuum chamber 20 is a cylindrical vacuum chamber 30 having an inner wall 40 and an outer wall 50, and defining a central volume 60.
  • the cylindrical vacuum chamber 30 is preferably made from an electrical insulator such as glass. However, other electrical insulators, such as ceramics or metal oxides, may be used without departing from the present invention.
  • the dimensions ofthe test model cylindrical vacuum chamber 30 are 10 cm in diameter and 61 cm long. However, other dimensions may be used without departing from the present invention.
  • X-rays are generated during the operation ofthe neutron/proton source 10 from Brensteshlung emission and by stray electrons striking metallic parts ofthe device. Because glass does not attenuate x-rays well, added lead shielding should be used to provide x-ray attenuation. However, only a thin layer of lead is necessary because X-rays are easily attenuated. X-ray attenuation can also be provided by any high-z material, such as ceramic, or by using leaded glass to make the cylindrical vacuum chamber 30.
  • Two anodes that are 100% transparent to oscillating particles 70 and 80 are located at either end ofthe cylindrical vacuum chamber 30 having axes coincident with the axis ofthe cylindrical vacuum chamber 30.
  • the two anodes 70 and 80 are substantially cylindrical and hollow anodes 90 and 100.
  • the cylindrical anodes 90 and 100 are 9 cm in diameter. However, another diameter may be used without departing from the present invention.
  • Reflectors 110 and 120 are located at either end ofthe cylindrical vacuum chamber 30 between the cylindrical anodes 90 and 100 and the ends ofthe cylindrical vacuum chamber 30, so that their centers lie on the axis ofthe cylindrical vacuum chamber 30.
  • the reflectors 110 and 120 are concave reflecting dishes 130 and 140 whose concave surfaces face the center ofthe cylindrical vacuum chamber 30.
  • the concave reflecting dishes 130 and 140 are electrically grounded.
  • the focal length ofthe concave reflecting dishes 130 and 140 is set to obtain good electron microchannel formulation, i.e. approximately the distance to the mouth ofthe cathode.
  • this anode configuration allows electrons to oscillate inside a positive electric potential created by the cylindrical anodes 90 and 100 and the concave reflecting dishes 130 and 140, rather than being lost after ionization.
  • This design serves six functions: (1) because the cylindrical anodes 90 and 100 are cylinders and their ends are uncovered, they are 100% transparent to oscillating particles (i.e.
  • both the cylindrical anodes 90 and 100 and the concave reflecting dishes 130 and 140 are made of stainless steel.
  • any material that can sustain a high temperature without much sputtering may be used.
  • Tungsten has been found to be a good material, but it is expensive.
  • a cathode that is 100% transparent to oscillating particles 150 is centered in the middle ofthe cylindrical vacuum chamber 30 having the same axis as the cylindrical vacuum chamber 30 and the cylindrical anodes 90 and 100.
  • the cathode 150 is a substantially cylindrical and hollow cathode 160, with a body that is solid throughout.
  • the cylindrical cathode 160 is made of stainless steel, and is 10 cm long and 9 cm in internal diameter.
  • any material that can sustain a high temperature without much sputtering, such as Tungsten, and any other dimensions may be used without departing from the present invention.
  • the cylindrical cathode 160 is electrically grounded. The role ofthe cylindrical cathode 160 is twofold.
  • the cylindrical cathode 160 is a cylinder and its ends are uncovered, it is 100% transparent to oscillating ions. This result reduces ion losses due to collisions of ions with the inner wall 40 ofthe cylindrical vacuum chamber 30, thereby reducing overheating and erosion ofthe cylindrical cathode 160 due to direct ion-cathode collisions, and allowing for better ion beam confinement.
  • a reactive gas is supplied to the cylindrical vacuum chamber 30 from an inlet 170 and discharged through an outlet 180.
  • the reactive gas used is a deuterium gas (for D- D reactions) or a mixture of deuterium and tritium gas.
  • any other fusionable mixture such as D- 3 He, may be used without departing from the present invention.
  • the outlet 180 is connected to a removable means for reducing the gas pressure 185 in the cylindrical vacuum chamber 30.
  • the removable means for reducing the gas pressure 185 is a turbo vacuum pump 190.
  • the cylindrical vacuum chamber 20 is initially pumped down to IO" 7 Ton pressure by the turbo vacuum pump 190 and then backfilled with gas to IO -4 Ton.
  • Other pressures may be used without departing from the present invention.
  • pressure varies with the voltage and the distance between the cathode and the anode. Thus, if the pressure is changed, either the voltage or the distance between the cylindrical cathode 160 and the cylindrical anodes 90 and 100 or both must be changed as well.
  • the reactive gas may either be slowly fed into the chamber with the turbo vacuum pump 190 valved down and running such that the desired pressure is maintained after the gas is added, or altematively the cylindrical vacuum chamber 30 may be sealed off with the contained gas at the desired pressure and the turbo vacuum pump 190 removed, as is discussed later.
  • special precautions to maintain gas pressure and purity such as getters and intemal gas reservoirs used in other sealed tube electronic devices, may be employed.
  • the means for applying an electric potential 200 is a positively- biased, high voltage power supply 210 connected by feedthroughs 220 and 230 attached to connectors 240 and 250 extending through the wall ofthe cylindrical vacuum chamber 30 to the cylindrical anodes 90 and 100.
  • a positively- biased, high voltage power supply 210 connected by feedthroughs 220 and 230 attached to connectors 240 and 250 extending through the wall ofthe cylindrical vacuum chamber 30 to the cylindrical anodes 90 and 100.
  • other means for supplying an electric potential may be used without departing from the present invention.
  • the means for applying an electric potential 200 may supply one of two types of current: (1) a steady state cu ⁇ ent or (2) a pulsed cu ⁇ ent.
  • a steady state cu ⁇ ent or (2) a pulsed cu ⁇ ent.
  • the remainder of this description discusses the operation ofthe neutron/proton source 10 using a means for supplying an electric potential 200 that supplies a steady state cu ⁇ ent.
  • a pulsed power supply may be used to obtain similar neutron yields as are achieved with steady state cu ⁇ ents, but using less power.
  • a high voltage, low cu ⁇ ent steady-state power supply is first used to maintain a plasma discharge.
  • a pulsed power supply connected to the appropriate electrodes then supplies pulses of cu ⁇ ent to the electrodes. This operation, as opposed to pulsing from a cold neutral gas condition, helps prevent arcing and enhances the ability to maintain a relatively constant voltage while the cu ⁇ ent is pulsed.
  • the pulsed power supply is a unit composed of a capacitive storage with a fast switch.
  • a 2- ⁇ F capacitor was employed with a switch comprising a hydrogen thyration triggered by an SCR-capacitor circuit.
  • other pulsed power supplies may be used without departing from the present invention.
  • pulsed power supply due to the cu ⁇ ent squared (or higher power) scaling of neutron yield, as is discussed below, pulsed operation provides an improved neutron yield per time averaged input power.
  • This principal is best illustrated by way of an example. Assume a 10 9 n/s yield for D-D reactions is achieved using 100 kV of voltage and a 15 mA cu ⁇ ent, i.e. 1.5 kW, steady state cu ⁇ ent input power. Switching to a 10 Hz pulse rate using 10 ⁇ sec wide pulses with a peak pulse cu ⁇ ent of 15 A provides a larger peak neutron rate, but the same IO 9 n/s time averaged rate calculated on the basis of I 2 scaling ofthe neutron rate during the pulse.
  • 10" 4 represents the duty cycle, i.e. the fractional time that the pulses are "on.”
  • the improvement in power efficiency with pulsed operation increases as the pulse width is decreased.
  • the repetition rate is increased and the duty cycle is decreased so as to achieve the maximum peak cu ⁇ ent during a pulse.
  • the pulse width in time must, however, be longer than the ion recirculation time in order to preserve good ion confinement.
  • the recirculation time depends on the geometry ofthe neutron/proton source 10 and the operation conditions.
  • the recirculation time for the test model operating under typical conditions is ofthe order of five (5) ⁇ sec.
  • the ten (10) ⁇ sec pulse width used in the example above meets the parameters established for the test model. Large variations in the recirculation time may occur, however, without departing from the present invention.
  • a pulsed neutron source is desired for certain applications ofthe neutron/proton source.
  • some neutron activation analyses utilize measurements of characteristic decay gamma rays emitted from short half-life isotopes created when the pulse of neutrons i ⁇ adiates the sample being investigated.
  • the cylindrical vacuum chamber 30 is initially evacuated to a low pressure by the turbo vacuum pump 190, and then backfilled with gas.
  • high positive voltage is biased to the cylindrical anodes 90 and 100.
  • the gas pressure used depends on the operation voltage. This high voltage will cause gas breakdown, separating ions from electrons in neutral atoms.
  • the separated ions and electrons are then accelerated by the cylindrical cathode 160 and cylindrical anodes 90 and 100 in opposite directions in the direction ofthe electric field created by the high voltage bias.
  • the electrons are accelerated towards the cylindrical anodes 90 and 100, simultaneously colliding with neutral atoms, thereby producing additional electron-ion pairs.
  • the electrons then oscillate within the positive potential wells created by the cylindrical anodes 90 and 100 and the concave reflecting dishes 130 and 140, ionizing still more neutral atoms and forming electron microchannels that help focus the ion beams.
  • the ions are accelerated towards the cylindrical cathode 160, reaching maximum speed as they travel through the cylindrical cathode 160. After exiting the cylindrical cathode 160, the ions are decelerated and eventually reach a full stop before reaching the cylindrical anodes 90 and 100. Immediately following the full stop, they are accelerated again in the reverse direction toward the cylindrical cathode 160. In this fashion, the ions oscillate back and forth along electric field lines many times until they are scattered out ofthe system by interparticle collisions. The ions are also forced into ion beams by the electron microchannels, further raising the neutron yield.
  • the ions reaching a sufficiently high speed will collide and fuse with neutral atoms and with other oscillating ions, producing neutrons.
  • the ions ionize background gas, producing secondary electrons. These electrons follow the same pattem as the electrons previously discussed.
  • deuterium gas is used, energetic neutrons are produced by D-D fusion reactions. If a mixture of deuterium and tritium gas is used, energetic neutrons are produced by D-T fusion reactions. Non-fusing ions either scatter or charge-exchange and eventually escape.
  • the applied voltage, i.e. the ion speed is selected to be near the energy co ⁇ esponding to the maximum fusion cross-section, generally 50-200 kV, or higher if appropriate electrical insulation is inco ⁇ orated.
  • the neutron yield per unit power input ofthe instant invention is greater than prior devices of this type because ofthe electron confinement in the positive potential wells, low ion loss, and good recirculating ion beam focusing.
  • the yield can be expressed by the equation R oc I 2 , where R is the neutron yield and I is the total recirculation ion-beam cu ⁇ ent.
  • the neutron yield can rise as high as 10 13 neutrons/second for D-D fusion reactions, and 10 15 neutrons/second for D- T fusion reactions.
  • Voltages up to 200 kV may be used with the instant invention, the limit set by the space required to insert appropriate insulating materials, which prevent arcing.
  • the user sets the voltage to achieve the maximum fusion cross section (i.e. 200 kV). Then, the user increases the cu ⁇ ent to achieve the maximum neutron yield.
  • a pulsed power supply can achieve the same time averaged neutron yield as with a steady state power supply, but use less input power in the process.
  • a neutron/proton source 10 with an alternate geometry, such as a rectangular geometry, may be employed without departing from the present invention.
  • the axial shape of the neutron/proton source 10 and its components may vary without departing from the present invention.
  • the cylindrical anodes 90 and 100 can have a larger diameter than the cylindrical cathode 160.
  • the neutron/proton source 10 can be used as a proton generator after two slight modifications to the neutron/proton source 10.
  • the gas used is D- 3 He, which produces high energy (approximately 14 MeV) protons and 3.5 MeV alpha particles.
  • the operating voltages are set slightly higher than that for the normal operation ofthe neutron/proton source 10 to approach the voltage equivalent to the energy at which the D- 3 He cross section peaks.
  • the proton emission rate will be close to the 2.5 MeV D-D neutron rate for an equivalent device with the same input power because the cross sections of D- 3 He and D-D are similar.
  • This embodiment has the advantage that with straightforward changes in the gas and voltage, the neutron/proton source 10 can be used as 2.5 MeV or 14 MeV neutron source, or as a 14 MeV proton source.
  • the cylindrical vacuum chamber 30 is initially evacuated to a low pressure, and then backfilled with gas.
  • the inlet 170 and outlet 180 are sealed airtight.
  • the process of starting the fusion reaction within the cylindrical vacuum chamber 30 is then done by the purchaser ofthe instant invention.
  • the neutron/proton source 10 may be shipped back to the manufacturer, who will again evacuate the cylindrical vacuum chamber 30, backfill it with gas, reseal the inlet 170 and the outlet 180, and send the neutron/proton source 10 back to the purchaser.
  • a means for generating a magnetic field in the axial direction 260 is attached to the outer wall 50 of said cylindrical vacuum chamber 30.
  • the means for generating a magnetic field in the axial direction 260 is a plurality of magnetic rings 270 encircling the outer wall 50 ofthe cylindrical vacuum chamber 30.
  • the magnetic rings 270 are permanent magnets with an outside radius larger than the inside radius ofthe cylindrical vacuum chamber 30.
  • other magnets such as electromagnets or superconducting magnets, and other dimensions may be used without departing from the present invention.
  • the magnetic rings 270 are preferably* placed next to one another with no distance between them in order to generate a uniform magnetic field 280. However, if the user wishes to save costs, the magnetic rings 270 may be spaced apart in order to use fewer rings.
  • the purpose ofthe magnetic rings 270 is to generate a magnetic field 280, which confines both ions and electrons in the radial direction. As a result, the loss rate of particles lost to the inner wall 40 ofthe cylindrical vacuum chamber 30 is reduced, thereby allowing for higher fusion reaction rates.
  • the strongest magnetic field possible given the practical problems of engineering the magnet into the system, is desirable. In the test model, the maximum field strength achievable using permanent magnets is approximately 4 Kgauss. However, other types of magnets may generate higher field strengths.
  • the first is a shear B-field 290, which is essentially a surface magnetic field lying next to the inner wall 40 ofthe cylindrical vacuum chamber 30 in the axial direction, enclosing the cylindrical plasma column (i.e. the ion and electron beams viewed macroscopically) .
  • the shear B-field 290 has a large magnetic field gradient ⁇ B between the inner wall 40 ofthe cylindrical vacuum chamber 30 and the cylindrical plasma column.
  • the shear B-field 290 provides a deflection force acting on all charged particles moving into it.
  • both electrons and ions are forced away from the inner wall 40 ofthe cylindrical vacuum chamber 30 in a radial direction toward the cylindrical plasma column, thereby creating more particle collisions, which increases the fusion reaction rate.
  • the shear B-field 290 prohibits charged particles from leaving the system up to a specified energy, E 0 , determined by the strength ofthe shear B-field 290.
  • the confinement improvement can be evaluated in terms of ⁇ p / ⁇ ⁇ > p , the ratio ofthe average time for a charged particle to be lost due to upscattering (i.e. interparticle collisions that send particles in the radial direction) up to energy E 0 to the average scattering-collision time, the scale of which is equivalent to the confinement time by a pure electrostatic field.
  • the ratio as derived in R.H. Cohen, et al., Nuc. Fusion 20, 1421 (1980) and P.J. Catto, et al., Phv.
  • Fluids 28, 352 (1985) may be expressed as ⁇ p hss/r P - P ⁇ exp (E 0 /E r ave ), where E r ave is the average particle energy in the radial direction.
  • ⁇ p ioss ⁇ P > 1 , indicating improved confinement.
  • Using the shear B-field increases the efficiency (i.e. reaction rates per unit power) ofthe invention by approximately a factor of 5 in typical operation.
  • the second magnetic field type compatible with this embodiment is a homogeneous B- field (not shown) , which is a magnetic field spread uniformly through out the cylindrical vacuum chamber 30 in the axial direction with a radial magnetic field gradient of zero.
  • the homogeneous B-field rotates the charged particles perpendicular to the homogeneous B-field, thereby slowing down the diffusion of particles, which increases the fusion reaction rate.
  • D D 0 1/(1 + ( ⁇ ) 2 ) for transverse (i.e. radial) diffusion, where T is the time interval between two successive collisions.
  • T the time interval between two successive collisions.
  • the confinement is improved by the factor of (1 + ( ⁇ eB/m) 2 ).
  • the resulting improvement in efficiency appears to be less than for the shear B-field 290. This configuration can be desirable, however, for certain applications.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Engineering & Computer Science (AREA)
  • Particle Accelerators (AREA)

Abstract

On décrit une source électrostatique de neutrons/protons obtenus par fusion et soumis à une accélération/recirculation, cette source énergétique comprenant une enceinte (20) à vide, creuse, de forme allongée le long de son axe. On a monté des réflecteurs (110, 120) au niveau des extrémités opposées de cette enceinte (20) de manière à ce que le centre de ceux-ci soit situé sur l'axe de l'enceinte. On a placé dans l'enceinte (20) à vide, entre les réflecteurs (110, 120), une cathode (150) qui est transparente à 100 % aux particules oscillantes, délimite un volume central et possède le même axe que celui de l'enceinte (20). On a également placé à proximité des extrémités opposées de ladite enceinte (20), entre les réflecteurs (110, 120) et la cathode (150), des anodes (90, 100) qui sont transparentes à 100 % aux particules et dont les axes coïncident avec celui de l'enceinte (20). On a encore monté des moyens (170) d'introduction de quantités régulées de gaz réactif. En outre, on a monté des moyens (210) d'application d'un potentiel électrique entre les anodes (90, 100), la cathode (150) et les réflecteurs (110, 120).
EP96922455A 1995-06-16 1996-06-13 Source electrostatique de neutrons/protons obtenus par fusion et soumis a une acceleration/circulation Withdrawn EP0871957A2 (fr)

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US491127 1983-05-03
US49112795A 1995-06-16 1995-06-16
PCT/US1996/010233 WO1997000519A2 (fr) 1995-06-16 1996-06-13 Source electrostatique de neutrons/protons obtenus par fusion et soumis a une acceleration/recirculation

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EP0871957A2 true EP0871957A2 (fr) 1998-10-21
EP0871957A4 EP0871957A4 (fr) 1998-10-21

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GB201304702D0 (en) * 2013-03-15 2013-05-01 Stanko Taras Combined electromagnetic oscillatory nuclear fusion method

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AU6332596A (en) 1997-01-15
WO1997000519A3 (fr) 1997-02-13
TW316314B (fr) 1997-09-21
WO1997000519A2 (fr) 1997-01-03
ZA964942B (en) 1997-01-23
EP0871957A4 (fr) 1998-10-21

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