RU2400687C2 - Ballistic unit with splitter - Google Patents

Abstract

FIELD: weapons and ammunition.

SUBSTANCE: proposed ballistic unit has its evacuated barrel muzzle face communicated with cylinder-conic adapter. Note here that conic adapter inlet cylinder receives plastic, e.g. polyethylene, buffer with inner bore diametre exceeding caliber of fired round. Fired round sabot represents two cups: outer cup made from plastic material (polyethylene, caprolan etc) and inner cup made from strong thermosoftening plastic material (phenylon, graphylon, polycarbonate) or light alloy with high specific strength (B-95, MA-4, "Д16-Т"). At high velocity of fired round, annular damper made from gradient or homogeneous material, for example porous copper, can be arranged between said plastic buffer. Note here that damper inner channel features taper section.

EFFECT: reduced length of ballistic unit.

2 cl, 1 dwg

Description

The invention relates to techniques for high-speed throwing in laboratory conditions and is intended for aeroballistic research and experiments on high-speed interaction of projectiles with obstacles. When conducting such experiments, models and impactors are usually accelerated in plastic pallets. Often it is necessary to separate the pallet from the missile element, which is a rather complicated problem. In addition, for some studies, it is undesirable to get into the ballistic track and throwing gas (the movement of models in reactive media, the study of the sensitivity of explosives to shock, etc.).

Various devices are known for separating (cutting off) a pallet. The simplest of them is a barrier made of cardboard or plywood [1]. In the event of a collision with such an obstacle, the pallet breaks up and its fragments lag behind the missile element. The effect of such a barrier on the missile element is negligible. However, the throwing gas flows almost completely into the track.

The closest in technical essence and application conditions is a ballistic installation, to the trunk of which the gas cutter and the pallet cutter are sequentially docked [2, 3]. The gas cutter has a chamber with holes that are closed with rubber plugs before firing. After the throwing assembly leaves the barrel, the throwing gas knocks out these plugs and the compartment is connected to the atmosphere, which allows reducing the amount of throwing gas entering the ballistic track. Separation of the elements of the split pan occurs with a conical cutter, and their dilution to the sides occurs due to aerodynamic forces. To do this, a pressure of 50 ... 100 mm Hg is set in the gas and pallets before the shot.

The disadvantages of the ballistic installation described above are as follows:

- the total length of the cutter is not less than 3 meters, which imposes a limitation on the length of the experimental room;

- the presence of pressure in the shutoffs for breeding in the direction of the elements of the split pan leads to braking also of the missile element;

- incomplete cut-off of the throwing gas, since a certain part of the throwing gas moving along the axis of the shot gets into the track after the throwing element or even in front of it;

- the possibility of falling into the track fragments of the pallet or ablation products of the barrel and the pallet.

The task of the invention is to reduce the length of the installation, reduce the braking of the missile element after exiting the barrel, completely cut off the throwing gas and the elements of the pallet.

The problem is solved in that the barrel of the ballistic installation in which the missile assembly is accelerated (the missile element in the pallet) is docked with a cylinder-conical nozzle, in which the diameter of the inlet cylindrical section is equal to the caliber of the barrel, and the outlet cylindrical section d _in = 1,2 ... 1,4d where d is the caliber of the missile element. A cylinder-conical buffer of plastic material, for example polyethylene, with an internal channel with a diameter of d _k = 1.1 ... 1.2d is inserted into the inlet of the cylinder-conical nozzle.

At throwing speeds of more than 2 km / s, a damper made of a gradient or uniform material with high energy absorption, for example, of porous copper, can be installed in front of the plastic buffer.

The pan of the missile assembly is made in the form of two glasses inserted one into the other. Moreover, the outer cup is made of soft plastic material, for example polyethylene, and the inner one is made of durable thermoplastic (phenylone, graphilon, polycarbonate) or a light alloy with high specific strength (V-95, MA-4, D16-T).

The braking of the pallet in a cylinder-conic nozzle with a length of the order of 0.3 ... 0.5 m instead of aerodynamic dilution of the pallet elements can significantly reduce the length of the ballistic installation and completely eliminate the penetration of throwing gas, as well as the ablation products of the barrel and the pallet into the track. In addition, this design allows research on high-speed collision "shooting at close range", which in turn allows you to significantly reduce the size of the experimental room. The diameters of the internal channel of the buffer and the output cylinder of the nozzle are selected from the condition of unobstructed span of the missile element under normal tolerances for misalignment and indirectness of the connection between the barrel and the nozzle.

The drawing shows an example implementation of the invention. The ballistic installation was created on the basis of the PPH 23/8 two-stage light gas installation [4] and includes a powder chamber 1 with an annular liner 2, a barrel 3, at the beginning of which there is a missile assembly consisting of an external 4 and an internal glass 5. In the internal glass 5 a cavity is made for the missile element 6. The barrel 3 is muzzle cut docked with a two-layer cylinder conical nozzle, in which the casing 7 is dressed on liner 8 by means of a hot landing. A buffer 9 is inserted into the cylinder-conical nozzles. An electromagnetic speed sensor 10 with a nozzle for connecting to a vacuum pump is inserted into the cylinder-conical nozzles. The muzzle section of the speed sensor 10 is hermetically sealed with Mylar or Mylar film 11, which is fixed by a pressure ring 12. An annular damper 13 with a conical inner channel can be located in front of the buffer 9.

The process of the shot is as follows. After the initiation of the powder charge in the powder chamber 1, the combustion products accelerate the missile assembly 4, 5, 6 in the barrel 3. The presence of an annular liner 2 in the powder chamber 1 allows you to select the required charge density of the powder charge, providing maximum reproducibility of the given speed for various throwing elements [5- 8]. After the contact of the outer glass 4 with the damper 13, the glass 4 begins to brake. After the inner cup 5 contacts the damper 13, the cup 5 also starts to slow down. The damper material is selected so that the speed of sound in it is higher than the speed of the missile assembly. This, as well as the conical shape of the channel of the damper allows you to more smoothly start accelerating the buffer 9. Throwing element 6, continuing to move at the same speed, flies through the channel of the plastic buffer 9, the output cylinder of the cylinder-conical nozzle 8, the channel of the electromagnetic sensor 10, breaks the polyester film 11, and is used further for experiments on high-speed interaction or in the aeroballistic track. After the damper 13 is fully compressed, the buffer 9 accelerates and moves in the cylinder-conical nozzle, its channel cools, which completely eliminates the possibility of the throwing gas, as well as any parts of the pallet, in the ballistic track. After the channel collapses and the buffer 9 approaches the output cylinder, it brakes and stops.

The proposed design of a ballistic installation with a cutoff of gases and pallets provides an “absolutely clean missile element” and can significantly reduce the experimental room. In addition, it provides a significant reduction in the sound of the shot and, practically, the complete absence of rollback of the ballistic installation. It is enough to install the barrel in mobile lunettes with rubber stops. And, finally, the propellant sealed in the barrel can be pumped directly into the ventilation system, which eliminates its entry into the experimental room.

Information sources

1. Zlatin N.A., Krasilshchikov A.P., Mishin G.I., Popov N.N. Ballistic installations and their application in experimental studies. M .: Nauka, 1974, 344 p.

2. Theoretical and experimental studies of hypersonic flows in the flow around bodies and in traces: Sat. articles./ Ed. G.G. Cherny, S.Yu. Chernyavsky. M .: Moscow Publishing House. state University, 1979.

3. Aeroballistic installation - a tool of modern experimental hypersonic aerodynamics. Report. / Institute of Mechanics, Moscow State University, No. 2032. Hand. topics Black G.G., Chernyavsky S.Yu. M .: 1977, 43 p.

4. Khristenko Yu.F. To the problem of increasing the survivability of two-stage ballistic installations. "Applied Mechanics and Technical Physics", 2000. V. 41, No. 6. S.153-160.

5. Khristenko Yu.F. Experimental studies of the main ballistic processes of light gas plants. Selected papers "All-Siberian Readings in Mathematics and Mechanics". Tomsk: ed. Tomsk University, 1997.V.2. Mechanics. S.207-213.

6. Khristenko Yu.F. Two-stage light gas installation. RF patent №2251063. Bull. No. 12, 2005.

7. Kulpin V.I., Sinyaev S.V., Khristenko Yu.F. Position and velocity sensor for fast-moving bodies. RF patent No. 2193207. Bull. No. 32, 2002.

8. Kulpin V.I., Sinyaev S.V., Khristenko Yu.F. Sensor of moment of flight and speed of movement of fast moving bodies. Application for invention No. 2005100882/28 (000968). Priority dated January 17, 2005.

Claims (2)

1. A ballistic installation, including an evacuated barrel, a missile assembly consisting of a missile element and a pallet, a throwing gas cutter and a pallet, characterized in that the cutter is made in the form of a cylinder-conical nozzle attached to the muzzle of the barrel, the output diameter of which is d _in = (1 , 2 ... 1,4) d, where d is the caliber of the missile element, and a plastic, for example, polyethylene, buffer with an internal channel with a diameter d _k = (1,1 ... 1,2) d is inserted into the inlet of the cylinder-conical nozzle, and the pallet is made in the form of external and inner cup, the outer cup is made of plastic material such as polyethylene, Caprolon and internal - of a durable thermoplastic material or light alloy. 2. Ballistic installation according to claim 1, characterized in that an annular damper made of a material with high energy absorption, for example, of porous copper, is placed in front of the plastic buffer, the inner channel of the damper being conical.