RU2110754C1 - Projectile - Google Patents

Abstract

FIELD: projectiles with devices for spin stabilization produced under the action of gases by means of rigidly attached fin assembly and inclined grooves. SUBSTANCE: projectile has a body with aerodynamic blades and gas turbine arranged on its surface. Aerodynamic blades, with a retainer mounted before them, are positioned on the back cone with under- cutting of the bottom section and inclined towards the centering helical bulges of the turbine separated by an annular groove. The height of the bulges is commensurable with the boundary layer thickness. EFFECT: enhanced accuracy of fire. 3 dwg

Description

 The invention relates to ammunition for smooth-bore artillery, in particular, to shells with devices for stabilizing flight by rotation generated under the influence of propellant gases by means of rigidly fixed plumage and inclined grooves.

 When firing from smooth-bore systems, the axial orientation of shells, mines and missiles on the flight path is carried out by aerodynamic stabilizers - folding spring-loaded blades (plumage), through which the center of pressure is shifted beyond the center of gravity of the munition [1, 2].

 A disadvantage of the known stabilization devices is the complexity of the cocking and opening mechanisms of the plumage blades and the timing of the operation from the location in the barrel, which reduces the functional reliability of the ammunition and the accuracy of fire.

 More progressive is the gyroscopic stabilization of projectiles in flight by rotation around the longitudinal axis, which is preliminarily carried out before firing the product in the bore or launching device by blowing propellant gases of the propellant charge of the multi-vane impeller [3, 4, 5, 6].

 A common drawback of these analogues is the complexity of the barrel launch system, which is not possible to practically use in standard firing systems.

 The noted drawback is eliminated in the design of shells, on whose side surface or on a pallet that separates after firing, spiral turbines, internal spiral cutting are used, which serve for the passage of gases of a burning propellant charge, which creates a rotational moment around the axis of the projectile, and / or plumage on the bottom to create aerodynamic stabilization of flight to the target [7, 8, 9, 10].

 The closest to the proposed projectile from among analogues in terms of coinciding features and technical nature is the design of the bullet according to [10], with a spiral thread on its front and bottom parts. The turbine on the lateral surface of the bottom part provides effective twisting around the longitudinal axis in the bore - gyroscopic stabilization, and the spiral blades of the rigidly fixed plumage on the front part increase the stability in flight by rotating the product with an aerodynamic free flow.

 The disadvantage of the prototype is the limited range due to the additional aerodynamic drag of the blades of the front of the bullet, which inevitably reduces the accuracy and range.

 The objective of the invention is to increase the tactical and technical characteristics of the ammunition: the initial velocity of the projectile, range and accuracy.

 The desired result is achieved by the fact that in the known projectile with aerodynamic blades and a gas-dynamic turbine on its surface according to the invention, aerodynamic blades, in front of which a latch is mounted, are placed on the inverse cone with undercutting of the bottom cut and are inclined to the centering spiral turbine protrusions separated by an annular groove, the height of which is comparable with a thickness of the boundary layer.

 Distinctive features, simple structural improvements of the known features and their new interconnection provide an increase in the initial velocity and range of the projectile due to the more productive use of the kinetic energy of the propellant gases of the propellant charge in the bore for gyroscopic stabilization by rotation and the organization of back air flows on the flight path, which reduces aerodynamic drag .

 Each essential feature is necessary, and their combination is sufficient to achieve a new technical result, which means that the effect of the sum is obtained, and not the sum of the effects.

 The invention provided an increase in the combat power of an artillery shell compared to a standard projectile due to the placement of additional explosive in its previous dimensions in place of the eliminated folding tail feather blades.

 Thus, each essential attribute is not known per se, but their totality represents the novelty of quality.

 Aerodynamic blades on the inverse cone of the bottom of the projectile form airflows and their distribution, and together with the rarefaction in the dull central hole of the bottom cut (undercut) of the projectile, they reduce movement resistance by 30%. The same blades during the movement of the projectile in the barrel direct the gas flow of the propellant charge at the optimal predetermined angle to the turbine blades, creating additional pressure for the axial rotation of the projectile.

 The latch creates an additional elastic support for the projectile in the breech of the barrel, providing power closure and alignment of the projectile in the barrel before firing at all angles of fire.

 Performing on the surface of the centering thickening of the projectile separated by an annular groove (receiver) of at least two turbines with a height lower than the thickness of the boundary aerodynamic flow provides an increase in torque in the barrel channel through gas compression in the receiver, reducing friction losses of the centering thickening due to gas lubrication, and eliminates trajectory inhibiting interaction of the turbine profile with the incoming air flow.

 The practical implementation of the proposed design of the projectile is available to a specialist in the field of ammunition production, and in the aggregate of features is unknown and does not explicitly follow from the prior art.

 In FIG. 1 shows a general view of the projectile; in FIG. 2 is a section along AA in FIG. one; in FIG. 3 is a view along arrow B in FIG. 2.

An example embodiment of the invention. On the side surface of the shell of a 1-gauge 125 mm shell for the D-81 tank gun, two centering thickenings are made — turbines 2, each containing 18 spiral channels 3 of 5.5 x 5.5 mm dimensions. The turbines 2 are separated by a receiver 4 formed by an annular groove, the volume of which is equal to the total volumes of their channels 3. The height of the turbine blades 3 is selected commensurate with the thickness of the boundary aerodynamic layer of the oncoming flow, which is uniquely related to the velocity of the projectile and is 5.5-6.0 mm. The number of turbines 2 and the volume ratio of the receivers 4 separating them is determined depending on the required initial speed and the required projectile range. For the described example, the volume of the receiver 4 is 8.5 cm ² . In the receiver 4 of a smaller volume creates additional pressure, that is, it acts as a compressor, which increases the angular velocity of rotation of the projectile.

 The bottom part of the projectile is made in the form of a truncated cone, on the side surface of which there are spiral blades 5, and in the end (small base) - a blind central hole 6 (rarefaction chamber), undercut of the bottom cut.

 Opposite the blades 5, spring clips 7 are strengthened, the profile of which is congruent to the conical surface of the gun barrel entry part. The blades 5 are strengthened at an angle to the spirals 3 of the turbines 2, which creates a gas-dynamic support of the gaseous products of combustion of the propellant charge.

 The shell operates as follows. The energy of the gaseous products of combustion of a propellant charge, the pressure of which in the barrel channel is 3.5 thousand atm, supplied to the blades 5, rotates the projectile and pushes it along the barrel. In the receiver 4, the accumulation of gases passing through the channels 3 of the first turbine 2, the equalization of pressure fluctuations with a pulsating flow and intermittent flow through the channels 3 of a smaller section, creates an additional torque. The total angular velocity of rotation of the projectile develops up to 16,000 rpm.

 On the flight path of the projectile at a speed of 2.5 M, turbines 2 do not have a braking effect, since they are located below the boundary aerodynamic layer 6.0 mm thick.

 The blades 5 perform the function of aerodynamic stabilization of the projectile by additional rotation (up to 7%) of the incoming air flow, which is leveled and accelerated in a given space by means of a rarefaction in the chamber 6 of the projectile bottom.

 As a result, compared with the standard 30F26 shell for the D-81 tank gun, an increase in the initial speed of 15%, firing accuracy of 1.2 times, while maintaining the flight range, is provided.

 The projectile is adapted for firing from standard gun and launch systems.

 The given example has only illustrative purposes and does not limit the scope of rights of the aggregate of essential features of the formula.

 So, there are possible options for the constructive implementation of gas-dynamic turbines in the form of centrifugal (with tangential channels of a centering thickening) or described axial, as well as their quantitative content both of the same type and in a combination of a given sequence, separated by receivers of the estimated volume to achieve the performance indicators presented to the projectile technical requirements.

 A centrifugal gas-dynamic turbine has the advantage of lower shape and drag coefficients, which helps to improve the ballistic characteristics of the projectile, flight stability and ultimately increase the firing range.

 Sources of information.

 1. Service manual (album of drawings), "100-mm anti-tank gun T-12." M.: Military Publishing House of the Ministry of Defense of the USSR, 1969, p. 92, fig. 93.

 2. Handbook of artillery ammunition ..., Russian-German joint venture "Nova", 1992, p. 131.

 3. US patent, 3610096, CL. F 41 F 3/04, 1971.

 4. US patent, 3946639, CL. F 41 F 3/00, publ. 03/30/76.

 5. German patent, 101270, nat. class 72c 16, 1898.

 6. Application Great Britain 8630852, CL F 41 F 3/048, publ. in bull. 87/21 from 05.20.87.

 7. US patent, 3610095, CL. F 41 F3 / 04, publ. 10/05/71.

 8. US patent, 4936216, CL. F 42 B 10/34 publ. 06/26/90.

 9. US patent, 4936318, cl. F 42 B 10/34 publ. 02/26/91.

 10. U.S. Patent 5133261, CL F 42 B 10/04, publ. 07/28/92 - prototype.

Claims (1)

 A projectile with aerodynamic blades and a gas-dynamic turbine on its surface, characterized in that the aerodynamic blades, in front of which the latch is mounted, are placed on the inverse cone with undercutting of the bottom cut and are inclined to the centering spiral turbine protrusions separated by an annular groove, the height of which is comparable with the thickness of the boundary layer.

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