RU2789675C1 - Method for assessing the damaging effect of anti-personnel mines of directed action - Google Patents

Abstract

FIELD: military technology.

SUBSTANCE: invention relates to a method for assessing the damaging effect of anti-personnel mines of directed action. At the first stage, a sector target situation is created at individual elementary sites and anti-personnel mine of directed action is detonated. At the second stage, the coordinate and numerical laws of destruction of the object under study are determined, the indicators of the damaging effect of fragments of an antipersonnel mine of directed action at various distances from the rupture site are calculated on the basis of empirical dependencies.

EFFECT: improving the accuracy of the initial data necessary for constructing the coordinate and numerical laws of destruction of the object under study, the possibility of calculating the indicators of the damaging effect of fragments at various distances from the site of the rupture of an antipersonnel mine of directed action, reducing the time and complexity of testing.

1 cl, 3 dwg, 4 tbl

Description

The invention relates to the field of mechanical engineering, in particular to the field of testing anti-personnel fragmentation mines of directed destruction (PMNP) to assess the effectiveness of the damaging effect.

There is a known method for determining the initial velocity of a fragment, which consists in explosively throwing a fragment in a given direction and determining the time it takes the fragment to fly the distance from the point of explosion to a certain screen, reducing the average velocity of the fragment to the initial velocity of the fragment using the equation of motion of its center of mass (A.N. Dorofeev, A. P. Morozov, R. S. Sarkisyan, Airborne Munitions (VVIA named after Prof. N. E. Zhukovsky, 1978, pp. 210-214).

A device is known for determining the initial speed of a fragment, containing a throwing device, a screen, a device for recording the time of flight of a fragment from the point of explosion to the screen (A.N. Dorofeev, A.P. Morozov, R.S. Sarkisyan. Aviation ammunition. VVIA named after prof. N.E. Zhukovsky, 1978, pp. 218-219).

The disadvantage of the above method and device is the lack of information content, since with their help only the initial velocity of one fragment is determined, but other characteristics of the ammunition fragmentation field are not determined.

A device for determining the characteristics of a fragmentation field of ammunition, consisting of ammunition, a semi-cylindrical target and an initiation device (A.N. Dorofeev, A.P. Morozov, R.S. Sarkisyan. Aviation ammunition. VVIA named after prof. N.E. Zhukovsky, 1978, pp. 210-214, 218-219, 228).

The disadvantage of the method and device is the lack of information content, since when using them, the speeds of the leading and trailing fragments, the average speed and depth of the fragmentation field of destruction are not determined.

A known method for determining the characteristics of a fragmentation field of ammunition, which consists in undermining an ammunition located horizontally in the center of a semi-cylindrical target using an initiation system, while the explosion of the ammunition is carried out in an explosion chamber, the time dependence of the filtered Doppler frequencies of the signals reflected from part of the fragmentation field is obtained relative to the moment of detonation ammunition. The disadvantage of the method and device is the lack of information content.

Closest to the invention is a method for determining the characteristics of the fragmentation field of ammunition, which consists in undermining the ammunition located horizontally in the center of a semi-cylindrical target, and subsequent calculations of the differential law of the distribution of fragments in the directions of expansion and the law of distribution of fragments by their masses (A.N. Dorofeev, A. P. Morozov, R. S. Sarkisyan, Aviation Munitions (VVIA named after Prof. N. E. Zhukovsky, 1978, pp. 210-214, 218-219, 228). The disadvantage of the method and device is the lack of information content.

The purpose of the tests in the proposed method is to determine the indicators of the damaging effect of fragments of PMNP at various distances from the place of mine rupture.

The technical problem to be solved by the claimed invention is to obtain the initial data necessary for constructing the coordinate and numerical laws of destruction of the object under study and calculating the indicators of the damaging effect of PMNP fragments at various distances from the rupture site, as well as reducing the time, laboriousness and cost of testing.

The technical result that can be obtained when solving a technical problem is to increase the accuracy of the initial data necessary to build the coordinate and numerical laws of destruction of the object under study and to calculate the indicators of the damaging effect of PMNP fragments at various distances from the rupture site (damage radii, the probability of hitting a target with taking into account the accepted defeat hypothesis), as well as in reducing the time, labor intensity and cost of testing through the use of empirical relationships that link indicators characterizing the damaging effect of PMNP with the values of its physical factors and the technical characteristics of the object under study, with the minimum required number of tests.

The set task with the achievement of the technical result is achieved by the fact that in the proposed method for assessing the damaging effect of PMNP, two stages are implemented - the first, where a sectoral target environment is created on separate elementary sites and the PMNP is undermined, and the second stage, which consists in determining the coordinate and numerical laws of defeat of the studied object, calculating the indicators of the damaging effect of PMNP fragments at various distances from the rupture site (damage radii, the probability of hitting the target, taking into account the accepted hypothesis of damage) with the minimum required number of tests.

At the first stage, to determine the characteristics of the distribution of lethal fragments in space, a sector target environment is created on individual elementary sites. For testing, wooden shields are installed with a size of about 3.0 × 2.5 m and a thickness of about 25 mm at distances of 10, 20, 30, 40, 50 and 60 m from the center and in width up to 60 m (or up to 100 m, or up to 200 m) in the frontal direction, depending on the type of mine. The sector of probable scattering of fragments for the target environment is up to 60 degrees (Fig. 1).

In the center of the sectors at a height of 1.5 m from the ground, the test PMNP is placed in such a way that the shields in the ball sector can intercept the fragments (the area of fragmentation when a mine is detonated with a directed strike, Fig. 1.). In FIG. 1 marked: A - the direction of expansion of the mine fragments; R is the distance from the place of explosion to the target; B - target area.

After the explosion of the PMNP, the total number of fragments that fell into the shields of the sector target environment is counted and the number of penetrations by the fragments of the shields, the depth of penetration of the fragments that have not penetrated the shields are counted.

In this case, a lethal fragment is a fragment capable of penetrating a dry pine or spruce board 2.5 cm thick, which corresponds to a specific kinetic energy of a fragment equal to 100 J/cm ² .

At the second stage, the coordinate (probability of hitting a single target with one PMNP fragment at a given distance R from the mine detonation point) and numerical (probability of hitting a single target when two or more fragments hit the target area) laws of destruction of the object under study are determined, the value of the efficiency index of the striking object is calculated actions of the PMNP for the object under study, additionally during the tests, the values of the parameters of the damaging effect of the PMNP are determined, the dependencies connecting the indicators characterizing the damaging effect of the PMNP with the values of its physical factors and the technical characteristics of the object under study are specified.

To calculate the density of lethal fragments Δ _y, the PMNP expansion area is represented as a spherical segment. This makes it possible to determine, depending on the range, the density of finished fragments and the probability of hitting the target (Fig. 2).

Within the area of damage, ready-made fragments scatter evenly.

Determination of the average density of finished fragments on the affected area:

where n ₀ - the number of lethal finished fragments

S - the area of the lesion;

where R is the distance from the explosion site to the target, m;

ϕ - angle of expansion of finished fragments, deg.;

h is the height of the spherical segment, m;

r - half of the base of the spherical sector, m.

Determination of the expansion velocity of finished fragments V _p by the expression:

where k _os is the expansion velocity reduction coefficient due to the use of ready-made fragments k _os = 0.77 ... 0.95;

η - explosion factor, defined as:

where m ₀ , n ₀ - mass and number of finished fragments;

D - mine explosive detonation speed, m/s;

W _BB - mass of explosive, kg.

Determination of the speed of the meeting of the fragment with the target by the expression:

- баллистический коэффициент готового осколка, м^-1.Where

- ballistic coefficient of the finished fragment, m ^-1 .

Determination of the ballistic coefficient by the expression:

where K ₀ is the shape factor of the finished fragment, determined empirically and equal to: for a ball K ₀ = 0.00193; for the cylinder K ₀ = 0.00266; for a rectangle K ₀ = 0.00277; for a rhombus K ₀ = 0.00351.

To assess the effectiveness of the fragmentation action of PMNP, the specific impulse (specific energy) of the fragments is calculated and compared with the required specific impulse (required specific energy) to break through the protection.

The value of the specific impulse for finished fragments of various masses is determined by the expression:

The value of specific energy is determined by the expression:

where S _m is the area of the midsection of the i-th fragment.

For fragments with different shapes, the midsection area is determined by:

- for a record with a rhombic base:

where a, b are the lengths of the bases of the rhombus, m;

ρ ₀ is the density of the fragment body material, kg/m ³ .

- for a cylinder:

;Where,

;

d ₁ , d ₂ - two mutually perpendicular diameters of the base of the cylinder.

- for the ball:

;Where

;

d ₁ , d ₂ , d ₃ - mutually perpendicular diameters of the ball.

Calculations continue until the determination of the value of the specific impulse, commensurate with the required (threshold), while the specific energy is similar, under the conditions:

или

or

Determination of the density of lethal finished fragments by the expression:

where N _i is the number of fragments flying in the i ball belt;

S _i - area of the i-th spherical segment of the sector;

ϕ _i - the boundaries of the angles of the i-th spherical segment of the sector from the axis of symmetry of the PMNP.

Determination of the probability of hitting a single target with one ready-made PMNP fragment at a given distance R from the mine detonation point (coordinate law of destruction) by the expression:

where Δ _y is the density of ready-made lethal fragments flying at the target;

S _c - the area of the vulnerable area of the target.

To assess the damaging effect of PMNP on wooden shields (as the equivalent of a target - a person) under various hypotheses of damage, it is proposed to use indicators in the form of damage radii not lower than a given degree of severity (radius of reliable damage; radius of continuous damage; radius of effective damage, radius of damage).

The radius of target destruction not less than a given degree of severity, taking into account experimental data, is determined by the empirical expression:

where _Кpor is the coefficient of the accepted lesion hypothesis (0.9 - for a reliable lesion of at least extremely severe severity; 0.7 - for a continuous lesion of at least severe severity; 0.5 - for an effective lesion of at least moderate severity; 0 ,2 - for a lesion with at least mild severity);

l - mine body width, cm;

h - mine body height, cm;

L - horizontal angle of the sector, deg.

An example of calculations of damage radii not lower than a given degree of severity for the MON-50 mine is given in Table. 1.

To assess the predicted probability of hitting a target from the radii of damage not lower than a given severity for PMNP, the following expression is defined:

Thus, after calculating the first criterion for the effectiveness of fragmentation mines in terms of manpower, namely, the probability of hitting manpower (expression 15), it is possible to determine the second criterion for the effectiveness of fragmentation mines, namely, the reduced area of destruction. The reduced lesion area (S _pr ) is understood as a conditional area equal to the integral

where S is the area of damage in the target plane;

P(S) is a function that characterizes the probability of hitting the target.

A feature of human lesions by anti-personnel fragmentation mines is the presence of multiple lesions when two or more fragments hit. To take into account the accumulation of damage in case of multiple hits for PMNP, a numerical law of hit is used in the form of calculating the probability of hitting a single target when two or more fragments hit the target area. The average number of fragments required to hit the target area with the numerical law of destruction is defined as:

where S is the projection area of the entire target onto a plane perpendicular to the direction of fragments flight (on the picture plane);

S ₁ - the plane of the vulnerable area of the target.

The numerical law of hitting the target has the form:

where m is the number of fragments hitting the target area, pcs.

The proposed new indicators (damage radii) for assessing the damaging effect of PMNP are substantiated by the authors, taking into account the accepted hypothesis of damage (Fig. 3).

It should be noted that the fragmentation damaging effect of PMNP is currently characterized by the radius of continuous damage, i.e. the distance from the place of explosion to the line where the probability of hitting the target is at least 70%, and the width of the zone of continuous destruction.

The authors carried out a comparative assessment of the indicators of the damaging effect of PMNP - calculated values with indicators for performance characteristics for mines (for PMNP MON-50 and MON-100). Tables 2 and 3 present baseline data for MON-50 and MON-100 mines. Table 4 presents the calculated indicators of the damaging effect of these mines and their indicators of the effectiveness of the damaging effect. Comparative analysis of the calculated parameters and the results of practical tests of these mines do not exceed 10%, which is a satisfactory accuracy.

Thus, the new features, which have significant differences according to the proposed method, are the following set of actions:

1. Undermine the PMNP in a sector target environment.

2. After the explosion of the PMNP, the total number of fragments that fell into the shields of the target environment is counted.

3. After the explosion of the PMNP, the number of penetrations by fragments of wooden shields is counted, the depth of penetration of fragments that have not penetrated the shields is measured.

4. Calculate indicators for assessing the damaging effect of PMNP for the accepted hypothesis of damage with the minimum required number of tests:

- the radius of a significant lesion (R _dp ) - a lesion with a probability of at least 90%,

- radius of effective damage (R _ep ) - defeat with a probability of at least 50%,

- damage radius (R _p ) - defeat with a probability of at least 20%,

- radius of scattering of fragments (R _ro ) - defeat with a probability of 0%.

5. Determine the probability of hitting the target for the coordinate law of hitting.

6. Determine the probability of hitting the target for the numerical law of hitting.

7. Determine the reduced area of the lesion.

Thus, the proposed invention in the form of a method for assessing the destructive effect of PMNP allows you to obtain a technical result, which consists in increasing the accuracy of the initial data necessary to build the coordinate and numerical laws of hitting a target object and calculating the indicators of the damaging effect of PMNP fragments at various distances from the rupture site (radii defeat, the probability of hitting the target for the accepted hypothesis of hitting), as well as in reducing the time, labor intensity and cost of testing through the use of empirical dependencies linking indicators characterizing the damaging effect of PMNP with the values of its physical factors and the technical characteristics of the object under study, with the minimum required number tests.

Method for assessing the damaging effect of anti-personnel mines of directed destruction

Claims (1)

A method for assessing the damaging effect of anti-personnel mines of directional destruction, at the first stage of which, from separate elementary sites, namely wooden shields 3.0 * 2.5 m in size and 25 mm thick, they create a sector target environment with a total length in the frontal direction of up to 200 m, the rows of which are located at a distance of 10, 20, 30, 40, 50 and 60 m from its center, and for a sector target environment, they provide a fragmentation sector of up to 60 degrees, detonate an anti-personnel mine of directed destruction from the center of the sector target environment at a height of 1.5 m from the ground with the direction of fragmentation of an anti-personnel mine of directional destruction into the target area, determine the total number of fragments falling into the shields of the sector target environment after detonation by the number of penetration and the depth of their penetration, measure the density of fragments on the affected area, the speed of expansion of the fragments, the speed of the meeting of the fragments with a view, ballistic coefficients fragmentation c, specific impulses and specific energies of fragments, and at the second stage, indicators of the damaging effect of fragments of an anti-personnel mine of directed destruction are calculated, including the radius of reliable destruction - the distance from the point of detonation within which it is possible to hit the target with a probability of at least 90%, the radius of continuous destruction is the distance from the point of detonation within which it is possible to hit the target with a probability of at least 70%, the radius of effective destruction is the distance from the point of detonation within which it is possible to hit the target with a probability of at least 50%, the radius of destruction is the distance from the point of detonation within which it is possible to hit the target with a probability of at least 20%, determine the coordinate law of destruction of the studied anti-personnel mine of directional destruction, that is, the probability of hitting a single target by one fragment of an anti-personnel mine of directed destruction at a given distance from the break point, determine the numerical law of the studied anti-personnel mine for example of direct destruction, that is, the probability of hitting a single target with two or more fragments of an anti-personnel mine of directed destruction at a given distance from the break point, and also determine the reduced area of destruction, that is, the area around the target, if it hits, the target is disabled with a probability of 100%.

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