RU2311720C1 - Segmental disk-charge magneto-explosive generator, method for its manufacture and assembly - Google Patents

Abstract

FIELD: pulse engineering; magnetic energy cumulation with magnetic flux compression by means of explosive-material shock wave.

SUBSTANCE: proposed generator has composite disk-charge shell installed in each magazine and assembled of set of U-shaped fragments of current-conductive material. Return current-carrying conductor is made in the form of set of parallel strips whose quantity depends on number of fragments of deformable conductive shell set apart within magazine with corrugated film insulation in-between. In addition, proposed method for magazine manufacture includes installation of T-section disk-charge supporting member into disk-shaped mold. Then liquid explosive material is poured into mold and cooled down. In the process shell fragments are cut out of thin-sheet conductive material, bent to obtain U-shape, and positioned through their parts open in inner radius on explosive disk charge to form composite shell of charge. After that magazines separated by insulating gaskets are installed on central conductor and film insulator in the form of round sheet with central hole is placed at output end of generator on outer surfaces of magazines. Then return current-carrying conductor strips are installed and insulator folds formed in the process are entered into clearances between return current-carrying conductor strips, and shielding cover is placed onto this structure.

EFFECT: enhanced reliability, simplified design of generator, enhanced electric strength of insulation, facilitated generator manufacture and assembly, as well as reduced cost of these procedures.

3 cl, 3 dwg

Description

The invention relates to the field of pulsed technology, in particular to the field of magnetic energy cumulation, where the magnetic flux is compressed using a shock wave of explosive (BB). Electromagnetic energy obtained in this way can be used for research in plasma physics, acceleration of plates and shells to high speeds, etc.

The famous "High-speed disk explosive magnetic generator" M.S. Protasov and others. Proceedings of the third international conference on the generation of megauss magnetic fields and related experiments. "Superstrong magnetic fields. Moscow," Nauka ", 1984, pp. 26-28. This explosive magnetic generator / VMG / has the form of a coaxial, the inner conductor of which, having a corrugated shape, is formed by a set of plates in the form of disks with a central hole, which interconnected by special rings alternately on the outer and inner radii. The inner cavity of the inner conductor is filled with explosives with an initiator in the center. There are two drawbacks to this generator. Firstly, the multi-ampere current immediately flows through such a corrugated shape into the main conductor during the entire operating time, including when the generator is being powered. As a result, complex, durable and laborious contact joints are required. Secondly, strong magnetic pressure, reaching a surface current density of ~ MA / cm. At the same time, 50 thousand atmospheres acts through a conductive wall on an explosive located in the inner cavity of the corrugated conductor, and due to the large pressure value, the detonation properties of the explosive deteriorate. This leads to unstable operation of the HMG at a high current density.

Closest to the claimed generator is the "Explosive Magnetic Generator" by L.N. Plyashkevich et al., Copyright certificate 1090226, Cl. IPC H02N 11/00, BI No. 17, 99 g. An explosive magnetic generator contains at least one cartridge, which consists of a deformable conductive shell with a disk explosive charge. The cassettes are mounted on the center conductor and are located between the two end conductive plates. At the same time, the conducting walls of the cartridge are isolated by an air gap from the central conductor, in the cavity of which a cylindrical explosive charge with an initiation system is located. The return conductor is installed in the peripheral part of the generator. The prototype device is a powerless generator. With the introduction of the initial flux, the magnetic field penetrates both the working deformable cavity of the generator and inside the part of the explosive charge. In this case, the pressure on the deformable disks is balanced, and the magnetic pressure is not transferred to the explosive when creating a magnetic flux. In contrast to the analog, the detonation properties of explosives do not deteriorate. The disadvantage of the prototype is the lack of reliability associated with the fact that the deformable conductive shell of each of the cassettes consists of several elements (disk plates connected to the outer radius by a conducting ring), contact joints with an generated current amplitude of several tens of millions of amperes become unstable and can be broken . The presence of high-current contact compounds also complicates the design of the VMG. In addition, the low dielectric strength of the generator insulation. The design of the VMG is not optimized so that it is possible to use film insulation, which has the highest electrical strength, provided that it is made from whole pieces, i.e. if there are no joints between the individual pieces of film insulation.

The closest method of manufacturing and assembling the inventive generator is the method described in the work "High-speed disk explosive magnetic generator". MS Protasov et al. Proceedings of the Third International Conference on the Generation of Mega-Gaussian Magnetic Fields and Related Experiments. "Superstrong magnetic fields. Moscow," Science ", 1984, pp. 26-28.

A method of manufacturing and assembling an explosive magnetic generator according to the prototype includes the manufacture of at least one cassette, installing cassettes on a central cylindrical conductor between the end conductive plates and laying the film insulation. In the manufacture of explosive disk charges, the installation of charges between the conductive walls of the cassettes, the connection of the conductive walls of the cassettes with rings on the outer radius, they are contacted by careful crimping of the parts, since they are close to the explosives and therefore the use of welding or pressing with great effort is unacceptable for safety reasons. Then a high-voltage insulator is made, for example, of a film, but with gluing of the film sections at the transitions from the cylindrical section to the disk section, the manufactured insulator is pulled onto a set of disk cassettes axially mounted one after another. The generator assembly is being completed by installing a tubular reverse current lead on top of the insulator, which connects the generator at one end to the source of the initial magnetic flux, and at the other to the load.

The disadvantage of this method is that during the operation of connecting the conductive walls of the cassettes with rings on the outer radius, the use of welding or pressing with great effort is unacceptable for safety reasons due to the close location of the explosive charges to the joints of the parts. Careful crimping of the conductive parts is carried out manually, which complicates the manufacture of the generator. In addition, the manufacture of an insulator with gluing sections of the film at the transitions from the cylindrical section to the disk section is also a very time-consuming operation. And the presence of glued joints reduces the reliability of the insulator and the dielectric strength of the insulator as a whole.

When creating this invention, the main objective was to create a simple design of the disk VMG and the method of its manufacture and assembly, which allows to reduce the complexity and cost of disk VMG.

The technical result in solving this problem is to increase the reliability, simplify the design of the VMG, increase the electrical strength of the insulation, as well as simplify and reduce the cost of manufacturing and assembly of the disk VMG.

The specified technical result is achieved in that in comparison with the known generator, which contains at least one cartridge, consisting of a conductive deformable shell with a disk explosive charge, and which are mounted on a central conductor with a cylindrical explosive charge and an initiation system, and located between two end conductive plates, a reverse current path installed in the peripheral part, in the inventive generator, a conductive disk charge sheath in each the cassette is made composite in the form of a set of fragments of a U-shaped form from conductive sheet material. The reverse current lead is made in the form of a set of parallel plates in the number of fragments of the deformable conductive shell in the cassette, which are installed at intervals relative to each other, and the film insulation between them is made in corrugated form.

The specified technical result is also achieved by the fact that in comparison with the known method of manufacturing and assembling a disk sector VMG, including the manufacture of at least one cartridge, the installation of cassettes on a central cylindrical conductor between the end conductive plates and the laying of film insulation in the inventive method for the manufacture of cassettes a disk element with a T-section is mounted in a disk form. Next, pour liquid explosives into a mold, cool it. In this case, the reamers of the shell fragments are cut out of a thin-sheet conductive material, bent to a U-shape, and parts that are open on the inner radius are put on the explosive disk charge, forming a composite charge shell. Cassettes with insulated spacers between them are installed on the central conductor, and a film insulator in the form of a round web with a central hole is laid from the output end of the generator with the institution on the outer surface of the cassettes. Then the plates of the reverse current conductor are laid, and the formed folds of the insulator are inserted into the gaps between the plates of the reverse current conductor and the structure is covered with a protective cover from the outside.

The fact that the conducting shell of the disk charge in each cartridge is made composite in the form of a set of U-shaped fragments of thin-sheet conductive material that are open on the inner radius by a part of the explosive disk charge, forming a composite conductive shell of the charge, this ensures that it is amplified up to several dozens of megaamperes the current flows through the conductive shell of the cartridge, without encountering contact connections. Indeed, the junction lines of the fragments used are located in the radial direction, i.e. along current flow lines. Therefore, contact joints that prevent the flow of super-strong current in the cassettes are absent. This increases the reliability and stability of the explosive magnetic generator. In addition, the absence of contact joints in the direction of current flow allows the conductive fragments of the cartridge to be made of very thin sheet material, the thickness of which only slightly exceeds the depth of the skin layer of the current flow, defined by the expression

where δ is the depth of the skin layer (effective thickness of the layer on the surface of the conductor through which the current flows), μ is the constant of the magnetic permeability of the vacuum, ρ is the specific resistance of the conductor, τ is the effective time of the deformation of the contour of the disk HMG by an explosive explosion. From the above expression it is seen that the thickness of the sheet material for the conductive fragments of the cassettes is sufficient 0.6 mm to make fragments of copper or 1 mm to make fragments of aluminum. This is approximately two times less than in the prototype, which saves material, and also eases the requirements for dies and reduces the cost of the manufacturing process of fragments of a U-shaped form. The implementation of the reverse current path in the form of a set of parallel plates installed at intervals relative to each other, allows you to make a high-voltage insulator VMG from a single round film of film. When installing a film insulator in the gap between disk cassettes and plates of the reverse current lead, starting from the end of the generator, the resulting folds of the film insulator are displayed in the gaps between the plates of the reverse current lead. Since the electric strength of multilayer film insulators is much higher than chiseled or cast insulators with a thickness equal to the total thickness of the film, this increases the electric strength of the VMG circuit and increases its reliability. It is also important that the parallel plates of the return conductor have freedom for some radial movement. This allows you to squeeze the layers of a multi-film insulator and due to this the gap can be used most effectively to accommodate the film insulation. The fact that in the manufacture of disk charges support elements of a T-shaped form are used from an inert material (for example, metal) installed in the casting form, this makes it possible to use the cheapest explosive compositions for disk charges, for example, TNT. Since such compositions do not have mechanical strength, the presence of an inert material support element in the charge provides its support on the central conductor.

Figure 1 shows the inventive disk sector VMG.

Figure 2 shows a cross section aa of a disk sector VMG.

Figure 3 shows a scan of the workpiece for the manufacture of a sector fragment of a conductive shell of a disk cassette.

In figure 1, 2, 3 are indicated:

1 - conductive cassette;

2 - disk charge of the explosive cartridge;

3 - central cylindrical conductor;

4 - cylindrical explosive charge;

5 - system for initiating explosive charge along the axis in the form of a chain of electric detonators;

6 - end conductive plates;

7 - reverse current lead;

8 - film insulation between the disk cassettes 1 and the return conductor 7;

9 - supporting element of the cartridge of a T-shaped section;

10 - load;

11 - power source by the initial magnetic flux;

12 - electric detonators for closing the input end conductive plate 6 with the return conductor 7;

13 - arrester;

14 is a scan of a fragment of a shell of a charge for a cartridge, when bent, it acquires a U-shape.

Disk sector VMG contains at least one disk cassette 1, each of which contains a conductive shell 14 and a disk charge 2. Disk cassettes 1 are mounted sequentially one after another on the central conductor 3 on the supporting elements 9 of a T-shaped section of inert material. The conducting shell of the disk charge in each cartridge is made composite in the form of a set of fragments of 14 U-shaped from a sheet of copper or aluminum with a thickness of 0.5-1 mm, which corresponds to the depth of penetration of the pulse current (skin layer) into the conductive walls. The conductive shells of the disk cassettes are open on the inner radius. Disk cassettes are separated from each other by gaps with dielectric gaskets (gaskets are not shown in gaps in the drawing so as not to clutter the drawing). The Central conductor 3 contains a cylindrical charge BB 4 with a chain of electric detonators 5 for its initiation along the axis simultaneously along the entire length. Through the end conductive plates 6 and the return conductor 7, the VMG is connected at one end to the source of the initial magnetic flux 11 through the spark gap 13, and at the other to the load 10. The return conductor 7 is made, as shown in figure 2, in the form of a set of parallel plates along the number of fragments of the conductive shell 1 disk cassettes. Parallel plates 7 are installed at intervals along the axis of the VMG. This made it possible to perform a high-voltage shaped insulator 8, separating the return conductor 7 from the disk cassettes 1, from an integral film dielectric material with a single hole for outputting current to the load. The resulting folds during the bending of the film insulator from the end part of the VMG to the cylindrical part made it possible to bring the return current conductor between the plates 7. Note that the gaps between the plates 7 of the reverse current path are directed along the direction of the current and therefore do not worsen the conditions for the passage of current. Electric detonators 12 are installed above the end plate 6 of the VMG. They serve to bridge the source 11 of the VMG feed with the initial magnetic flux so that the generated energy does not return to the source 11, but is transmitted completely to the load 10.

A method of manufacturing and assembling a disk sector VMG begins with the manufacture of disk cassettes 1. In the manufacture of disk cassettes, charges 2 are first made from an explosive composition of TNT with hexogen, the melting point of which is 82 ° C. In the manufacture of the charge, first, a disk support element 9 of a T-section made of an inert material, for example, steel, is installed in the casting mold. Then the molten explosive composition is poured into the mold. After cooling, the explosive solidifies, and the T-shaped support element 9 provides charges 2 with the necessary strength and support for the cartridge. Then, from the sheet of copper or aluminum with a thickness of 0.5 ... 1 mm, the reamers of sector fragments are cut out and bent to a U-shape. Then put sector fragments 14 on the disk charge 2 from the outer radius and fix them on the charge 2 with glue. Sector fragments 14 on the inner radius remain normally open. The next step is to install the assembled cassettes 1 on the central conductor 3, separating the cassettes from each other with insulating spacers (for example, from cardboard) with a thickness of 1 ... 2 mm. Then, blanks are cut out of the polyethylene film in the form of at least one round web with a central hole for the load conductor and put on, starting from the output end of the VMG end to the load, followed by folding of free sections of the film onto the cylindrical surface of the cassettes. To enhance the electric strength, you can use a package of cut films with a total thickness of the order of 1.5 mm. Note that the electric strength of such a multi-film insulator 8 is quite large and amounts to about 300 kV.

The VMG assembly is completed by installing over the insulator 8 parallel plates 7 of the reverse current lead, attaching them at one end to the source of the initial magnetic flux 11, and at the other to the load 10. The resulting folds of the film insulator 8 are released into the spaces between the parallel plates 7 and cover the structure with a protective cover outside.

The inventive generator operates as follows.

Initially, the source 11 of the initial magnetic flux is discharged, and the electric circuit of the HMG is fed with the initial magnetic flux. It is convenient to use a capacitor bank as the source 11 of the initial magnetic flux. When the source 11 is discharged, the current in the VMG circuit flows through the central conductor 3, then through the load 10 and returns to the source 11 through the plates of the return conductor 7. Note that, since the conductive shells of 14 cassettes 1 are open on the inner radius, the current through the shells of 14 cassettes at the stage of feeding does not pass and the pressure of the magnetic field on the conductive shells and on the explosive charges in the cassettes does not act. At the maximum of the discharge current from the power source 11, the detonators 12 are simultaneously blown up on the input conductive plate 6 and the detonator chains 5 in a cylindrical charge 4. The explosion of the detonators 12 closes the input conductive plate 6 with the plates 7 of the reverse current lead. After that, the VMG circuit is connected through the end plates 6 only to the payload 10. An explosion of the detonator chain 5 initiates an explosion of a cylindrical charge 4, the explosion of which radially expands the walls of the central conductor 3. The expanding walls of the central conductor 3 close the shells of the disk cassettes from the inner radius and detonation of disk charges 2 is simultaneously excited by shock in all disk cassettes simultaneously.

The detonation of disk charges 2 propagates radially with a detonation velocity of the order of 8 km / s, and the walls of the seeing shells of disk cassettes under the action of an explosion of disk charges 2 scatter conically towards each other. The dynamic point of the meeting of the walls moves in the direction of increasing radius, that is, to the reverse current path. Moreover, the walls of all disk cassettes at the same time quickly displace the magnetic flux into the load.

When the magnetic flux is displaced, the walls of the cassettes work against the magnetic flux, as a result of which the magnetic energy in the circuit and, as a result, the current rapidly increase and are transferred to the payload 10 through the plates of the return current conductor.

An example of the implementation of the inventive design of the generator is the development of the model of the proposed VMG with ten cassettes with a diameter of 200 mm with a total length of 400 mm. Such a relatively small generator at a current of supply from the source of the initial flow of 4 million amperes amplifies the current by 9.5 times and creates a current pulse with an amplitude of 35 million amperes in a payload with an inductance of 5 nH.

An example of the implementation of the proposed method is the manufacture and assembly of a model with cassettes with a diameter of 200 mm The manufacture of disk cassettes with conductive shells in the form of a set of sector fragments of a U-shape made from continuous fragments of a thin 1 mm thick aluminum sheet is much simpler than in the prototype, since there is no operation for making high-current contacts. The operation of manufacturing a high-voltage insulator from an insulating film is also simple in comparison with the prototype, since due to the output of the formed folds between the parallel plates of the reverse current conductor, it is possible to manufacture a high-voltage insulator from continuous film webs. The continuity of the conductive shells in the cassettes and the manufacture of an insulator from a continuous sheet of film increases the reliability of the VMG.

Thus, in comparison with the prototype, the claimed invention allows to simplify the design of the VMG, increase the insulation strength, reduce the complexity of the manufacturing process and increase the reliability of the generator as a whole.

Claims (4)

1. Disk sector explosive magnetic generator containing at least one cartridge, consisting of a deformable conductive shell with a disk explosive charge, mounted on a central conductor with a cylindrical explosive charge and an initiation system and located between two end conductive plates, a reverse current conducting installed in the peripheral part of the generator, characterized in that the disk charge shell in each cartridge is made integral in the form of a set of fragments of the P-image heat form from sheet conductive material. 2. The generator according to claim 1, characterized in that the return conductor is made in the form of a set of parallel plates in the number of fragments of cassettes of the deformable conductive shell in the cassette installed at intervals relative to each other, and the film insulation between them is made in corrugated form. 3. A method of manufacturing and assembling a disk sector explosive magnetic generator, comprising manufacturing at least one cartridge, installing cartridges on a central cylindrical conductor between the end conductive plates and laying film insulation, characterized in that in the manufacture of cartridges a disk with T is installed the support element is filled with a cross-section and the explosive is poured, cooled, while the reamers of the shell fragments are cut out of the thin-sheet conductive material, I bend t them to a U-shaped and open parts on the inner radius, put on the disk charge of the explosive, forming a composite shell of the charge, then install cassettes with insulated spacers between them on the Central conductor. 4. The method according to claim 3, characterized in that the film insulator in the form of a round web with a hole for supplying load is laid from the output end of the generator with the institution on the outer surface of the cassettes, then the reverse conductor plates are laid, and the formed insulator folds are inserted into the gaps between the plates reverse current lead and then close the structure with a protective cover on the outside.

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