RU2711529C1 - Method for protection against air shock wave of vehicle - Google Patents

Abstract

FIELD: motor vehicle industry.SUBSTANCE: invention relates to motor transport, can be used in trucks with armored cargo platform. Method of protection against air shock wave of vehicle with armored cargo platform under body tent includes installation of masking cover on vehicle. In vehicle camouflage cover there used is web from fine-meshed network with frequent arrangement of camouflage elements, gap between vehicle cabin and masking network, as well as gap between cab and body tent is filled with air-mechanical foam with high foam mass stability. Gaps are filled with foam mainly after receiving information on threat of use of fire weapons by vehicle. Foam generator used is fire truck.EFFECT: attenuation of air shock wave acting on vehicle cabin, provision of cab stability in foam mass, equal to strength of armored cargo platform.1 cl, 1 dwg

Description

The invention relates to vehicles, can be used in trucks with an armored cargo platform.

. Ударная волна такой интенсивностью может нанести бронированной грузовой платформе средние разрушения.For transportation of discharge goods, as a rule, cars with an armored loading platform under a body awning are used [see Car transport NG9T1-01. Technical description and instruction manual. - FSUE “Design Bureau of Motor Transport Equipment”, 1990, 14 l.] (Hereinafter - the car). The main damaging factor of such cars during the explosion of conventional ammunition (air bombs, warheads of missiles) are shock waves propagating in the environment surrounding the munition, as well as high-speed fragments generated during the destruction of the shell of the explosive charge of ammunition. The risk of flying fragments can be minimized with shields that capture fragments. As such a screen, catching fragments flying in the direction of the cargo transported by car, can serve as a booking of the cargo platform. Therefore, its main striking factor is the air shock wave, the impact of which on the cargo platform of the car causes the latter damage of varying severity. The convoy transporting the discharge cargo includes technical means and personnel capable of repairing minor damage to vehicles, including their loading platforms. Therefore, the critical value of the resistance of an armored cargo platform to an air shock wave (by analogy to the resistance of a wheeled armored personnel carrier) can be considered the mathematical expectation of excess pressure in the wave front

. A shock wave of such intensity can cause medium damage to an armored cargo platform.

избыточное давление во фронте воздушной ударной волны при контактном взрыве боевой части КР «Томахок», рассчитанное по зависимости [см. Покровский Г.И. Взрыв. 4-е изд. Перераб. и доп. М., Недра, 1980, 190 с.]Since the dispersal areas of the convoy with discharge cargo are located mainly far from the line of possible contact between the conflicting parties, the most likely scenario for the use of conventional weapons against the convoy’s cars is their firing with Tomahok-type cruise missiles (hereinafter CR) without the entry of KR carriers into the territorial and object air defense zones. The mass of the explosive of the warhead of the Kyrgyz Republic is 120 kg, the main probable deviations of the Kyrgyz Republic in the longitudinal At a given distance

overpressure in the front of an air shock wave during a contact explosion of the warhead of the Kyrgyz Republic “Tomahok”, calculated according to the dependence [see Pokrovsky G.I. Explosion. 4th ed. Re-worker. and add. M., Nedra, 1980, 190 pp.]

, r - расстояние, м; m - масса ВВ, кг,Where

, r is the distance, m; m is the mass of explosives, kg,

. Такая интенсивность воздушной ударной волны, воздействующей на кабину автомобиля имеет место при контактном взрыве указанного боеприпаса на удалении от кабины порядка 21 м. Поэтому радиус поражения автомобиля в целом следует считать по его «слабому звену» - кабине автомобиля. Моторный отсек автомобиля также не имеет бронирование. Однако когда защищена от ударной волны кабина, то и находящийся под ней моторный отсек также будет защищен. Кроме того, эксперименты свидетельствуют, что двигатель получившего сильные повреждения автомобиля остается в пригодном состоянии, и после взрыва эти автомобили могут двигаться своим ходом [см. Действие ядерного взрыва (Перевод с английского), военное издательство Министерства обороны СССР, М, 1963].will be 1.5 kg / cm ² . Such an intensity of an air shock wave corresponds to a distance of 14 m. However, the car cabin does not have a reservation. The average destruction of the cabin of a military truck of the NG-9T1 type as occurs when

. Such an intensity of an air shock wave acting on a car’s cabin takes place during a contact explosion of the indicated ammunition at a distance of about 21 m from the cabin. Therefore, the radius of damage to the vehicle as a whole should be calculated from its “weak link” - the vehicle’s cabin. The engine compartment of the car also does not have a reservation. However, when the cab is protected from the shock wave, the engine compartment below it will also be protected. In addition, experiments indicate that the engine of a vehicle that has been severely damaged remains in good condition, and after the explosion, these cars can move on their own [see The action of a nuclear explosion (Translated from English), military publishing house of the Ministry of Defense of the USSR, M, 1963].

In order for the car to be equally resistant to the effects of an air shock wave, its cab must have additional physical protection. But her physical protection in the form of a reservation can lead to negative consequences. The mass of the equipped vehicle NG9-T1 with an armored cargo platform exceeds 11 tons. This does not allow booking his cabin, with a length of 1890 mm, a height of 2850 mm and a width of 2820 mm, heavy steel screens. Otherwise, cars with cargo could not move on low category roads.

It was possible to protect these vehicles from an air shock wave by placing them in pre-fabricated field fortifications [see RF patent No. 2568251 "Monolith", IPC: B63G 13/00]. The advantage of this method is the ability to create earthen sprinkling in the shortest possible time using local building materials. But the disadvantage of this method of protection is the impossibility to erect such a shelter for each automobile convoy as soon as possible .. The construction of one large quick-mountable field fortification for several cars with the above accuracy of the Tomahok KR and the dimensions of the cars will not reduce the likelihood of damage to closely located cars when hit KR "Tomahok" in a shelter from above.

A solution that partially eliminates the disadvantages inherent in the protection of automobiles by a quick-mounted field fortification may be a technical solution, including the placement of barriers from a gas-liquid medium around the car cabin. In this solution, a waterproof shell filled with hollow spheres and / or pieces of foam with water is used as an obstacle [see RF patent No. 2030708 "Method of damping an air shock wave", F42D 5/045 (means of absorption or damping of blast waves)]. The basis of this technical solution is the principle of attenuation of shock waves by creating a relaxation medium on the path of shock wave propagation [see Protection of passenger airliners from explosive loads: B.E. Gelfand, M.V. Silnikov, A.I. Mikhailin, M.V. Chernyshov (NGO Special Materials), “Technical Means of Countering Terrorist and Criminal Explosions”: Proceedings of the Sixth International Scientific and Practical Conference, October 2010 SPb University of the State Fire Service of the Ministry of Emergencies of Russia]. The method of creating a relaxation medium for attenuating the shock wave is implemented in the explosion locators of the Fontan family. The practice of using Fontan locators has shown that they minimize destruction and human casualties, effectively suppress the explosive, fragmentation, thermal and thermobaric effects of the explosion, repeatedly reduce the pressure amplitude at the front of the shock wave, erode and flatten the front of the shock wave, prevent fires, thermal and thermobaric lesions, reduce fragmentation flow.

However, the conditions and limitations under which the Fontan explosion localizer operates do not correspond to the conditions of the impact of an air shock wave on the vehicles in question. In the explosion locator "Fountain" the source of the shock wave - explosive is placed practically inside the dispersant, which, in turn, is placed ready-made in an airtight container. The mass of explosives does not exceed several kg. In the case of car protection from an air shock wave, its source is placed at a certain distance from the car in free air, and the explosive mass exceeds 100 kg.

A technical solution to reduce the intensity of the shock wave affecting the car in question could be a solution [see USSR author's certificate No. 1268741, 1986. “A method for localizing a gas explosion during the extinguishing of underground fires”, cl. E21F 5/00]. It allows you to increase the efficiency of localization of the shock wave by providing conditions for its self-quenching. For this, with a threatening increase in gas concentration to an explosive limit in a dead end mine, a foam plug is erected from gel-like foam with a variable multiplicity along the length of the foam plug. The foam multiplicity varies smoothly from a larger foam multiplicity from the side of the fire to its smaller value or discrete alternating foam strips of a greater and lesser multiplicity. An air gap is formed between the working roof and the upper surface of the foam plug. Through it, the removal of fire gases from the isolated part of the output. The shock wave propagating through the foam plug with alternating sections of varying lengths generates a series of counterpropagating shock waves, between which there is a rarefaction wave. The oncoming shock wave inhibits the entrained air flow and reduces its speed. The rarefaction wave propagating after it reduces the pressure in this air stream. The disadvantage of this solution in relation to vehicle protection is that the shockwave approach to the vehicle occurs in free air from any direction. Therefore, it is impossible to erect and hold the above foam plug in the free air around the car.

A technical solution to reduce the intensity of an air shock wave could be a solution [see RF patent No. 2030708 "Method of damping air shock waves during blasting operations", IPC: F42D 5/045]. This solution partially eliminated the disadvantage associated with the impossibility of erecting and holding a foam plug with a variable multiplicity along its length.

For this, a gas-liquid medium is obtained by placing in a waterproof shell hollow spheres or pieces of closed-cell foam with subsequent filling of water in the space free from loading solids placed with tight packaging. After performing these operations, the shell is sealed (tying the edge of the polymer shell in the forelock). According to the law of packing balls of the same size, the volume of free space between the balls to fill it with water is 50% and the density of the gas-liquid medium is 0.5 t / m ³ . When placed in the free space between the balls of the hollow spheres of a smaller size (with a ratio of ball diameters of 1/8 or less), the air content will be increased to 75% and the density of the gas-liquid medium will decrease to 0.25 t / m ³ . By using pieces of closed-cell foam, the air content in the barrier to the passage of the shock wave can be increased due to a denser packing of pieces of arbitrary shape. The range of regulation of the density of the gas-liquid barrier can be increased by using mixtures of hollow polymer spheres and pieces of foam. However, the disadvantage of this solution for the car in question is the need to include additional vehicles for the transportation of these spheres, pieces of polystyrene foam and water, as well as the relatively high time spent on performing a limited number of personnel to place them in waterproof containers. In addition, the resumption of the movement of the car requires a lot of time spent on disassembling the gas-liquid medium.

The closest technical solution to reduce the impact of conventional ammunition on the cabin and the engine compartment of the car, the decision is made [see Selivanov V.V., Kobylkin I.F., Novikov S.A. Explosive technologies: Textbook for technical colleges / Ed. V.V. Selivanova - M: Publishing House of MSTU. N.E. Bauman, 2008 - 648 pp., Ill. (l. 550)].

In this solution, conventional fire foam obtained using air barrels or foam generators is used to attenuate the effects of the shock wave. In order to prevent foam from spreading, a special frame is constructed, covered with a plastic film. Take into account the parameter characterizing the air-mechanical foam - its resistance, i.e. ability to persist for a certain time. The resistance value depends on the type of foaming agent, its concentration in the solution and the structure of the foam.

To carry out foam protection during blasting operations at the Central Research Institute of Fire Protection under the order of the RFNC-VNIIEF, a mobile foaming unit was developed consisting of a highly walkable tank truck and a hydraulic turbine foam generator with the following characteristics: foam capacity of 2200 l / s, the maximum distance from the installation to the place of foam supply 320 m, the height of the array of stable foam is 3 m, the resistance of the array of foam is ~ 1 hour.

The advantage of this technical solution is a significant weakening of the intensity of the air shock wave by a relatively small thickness of the foam layer and the high resistance of the foam, which allows preserving the protective properties of the foam over a period of time when the use of means of destruction by a special tactical group is most likely. However, if in the prototype solution the source of the air shock wave is located inside the foam layer, then the car must be protected when approaching the shock wave generated in free air. In addition, the construction of a special frame covered with plastic wrap requires the inclusion of an additional motor vehicle column for transporting the frame parts, as well as the relatively high time required to carry out a limited number of personnel for its construction on each vehicle with a discharge load.

The aim of the claimed invention is to eliminate the noted drawbacks, namely, the weakening of the air shock wave acting on the car cabin, ensuring the cabin stability in the foam array, equal to the resistance of the armored cargo platform of the car.

The technical result is achieved by performing additional new operations in the construction of a camouflage shelter for a car with an armored loading platform under a body tarpaulin, including installing a camouflage shelter on a car, consisting in the fact that in a camouflage shelter of a car a fine-mesh network with a frequent arrangement of camouflage elements is used, the gap between the car cab and camouflage net, as well as the gap between the cab and the body awning, are filled with air-mechanical foam with a high Coy array foam stability, foam and fill the gaps begin advantageously after receiving information about the threat of the use of car firing weapons, and as the foam generator used fire tanker truck.

The idea of the proposed technical solution is to use air-mechanical foam obtained by known foam generators to attenuate an air shock wave [see A.A. Everyone, D.F. Balta. “Design Features of a High-Pressure Foam Generator”: ISSN 0130-1268- Scientific Herald of the Respirator Scientific Research Institute of Hydromechanics, - 2015. - Vol. 52]. As an obstacle to the spreading of foam, use the internal cavity of the camouflage shelter erected above the car.

We show the materiality of the distinguishing features.

Filling the gap between the cab and the camouflage net, as well as the gap between the cab and the body tent with air-mechanical foam with high resistance to the foam mass, is a new solution. It prevents the spread of foam without the use of additional devices to hold the foam.

Using as a foam generator to fill the gaps with foam of a fire truck is a new solution. This ensures the supply of foam to the indicated gaps of the fire truck included in the convoy without the involvement of additional technical means.

снижение давления ударной волны, распространяющейся в пене,

, по отношению к давлению ударной волны, распространяющейся в воздухе,

, может быть представлено в виде линейного соотношения [см. Гельфанд Б.Е., Сильников М.В. Фугасные эффекты взрывов. СПб.: Полигон, 2002.]:Foam attenuation of an air shock wave, the source of which is the explosion of conventional ammunition, is a new solution. It provides the stability of the cabin, equal to the resistance of the armored cargo platform. Depending on the density of the foam,

pressure reduction of the shock wave propagating in the foam,

, in relation to the pressure of a shock wave propagating in air,

, can be represented as a linear relation [see Gelfand B.E., Silnikov M.V. High explosive effects. SPb .: Polygon, 2002.]:

и

fair when

and

,

,where R is the reduced distance

,

,

r is the distance to the source of the air shock wave, m,

m is the mass of explosive kg.

Based on the above ratio, it can be concluded that a foam layer with a thickness of 0.8 R can weaken the intensity of the air shock wave up to 16 times. In the case of an explosion of an explosive weighing 120 kg, this foam layer thickness is about 3.9 m. But then, when the above explosive is blown up on a safe platform for armored cargo platform at a distance of 14 m, the intensity of the shock wave approaching the outer boundary of the foam layer surrounding the car cabin will be 3.35 kg / cm ² . Therefore, in order for the intensity of the shock wave passing through the foam layer to correspond to the stability of the car cab 0.72 kg / cm ² it should be weakened no more than 4.7 times. This can be achieved by creating a foam layer with a density of only 4.9 kg / m ³ around the cabin. In this case, the total volume of the foam layer at its height corresponding to the height of the car, equal to 3 m, will be ~ 230 m ³ . To create such a layer of foam, ~ 700 kg of water with a foaming agent will be required. Then one ATs-5-40 fire tanker can provide foam protection for 7 cars. This solution provides a reduction in the time of erection of foam protection. In addition, the foam practically does not prevent the vehicle from starting to move after removing the camouflage cover.

The start of filling the gaps between the cabin and the camouflage net with foam, mainly after receiving information about the threat of using fire weapons in a vehicle, is a new solution. It allows, taking into account the time of erection of foam protection and the durability of the foam array, to erect and hold foam protection until a possible approach of the air shock wave to the protected vehicle. For example, if the launch of the KR “Tomahok” was carried out at a distance of 1000 km from the dispersal area of the convoy, then at a speed of KR 0.8 M in the indicated area they can be expected in about an hour. This margin of time, taking into account the delay time of obtaining information on the launch of the CR, is enough to create foamy protection for the car.

The drawing shows a diagram of a method of protecting a car from an air shock wave, which includes:

1 - cab type NG9-T1, 2 - engine compartment, 3 - body tent,

4 - camouflage net, 5 - nozzle (sprayer) of the foam generator,

6 - array of air-mechanical foam

Protection of the car from an air shock wave is as follows. In the area of dispersal of the convoy during the construction of the camouflage cover of the car, camouflage net 4 additionally forms a gap of 3.9 m between the cab of car 1 and camouflage net 4, as well as the gap between cab 1 and awning 4. Receive information about the enemy launching air attack means. Based on the information received, a decision is made to fill the specified gaps with foam. A nozzle (sprayer) 5 of the foam generator is introduced into the formed gap between the cabin and the camouflage net and filled with foam. If necessary, immediately begin the movement of the car disassemble the camouflage shelter, remove the foam from the sight glass of the cab 1 of the car and leave the array of foam. The remaining foam on the car is blown away by the oncoming air stream while the car is moving.

Thus, based on the analysis of the scheme of the proposed technical solution, we can conclude that the proposed method of protecting a car from an air shock wave has advantages that meet the intended purpose, namely, attenuation of the intensity of an air shock wave acting on a car cabin, ensuring the cabin stability in a foam array equal to durability of the armored cargo platform.

Claims (1)

A method of protection against an air shock wave of a car with an armored loading platform under a body tarpaulin, including installing a camouflage shelter on a car, characterized in that in the camouflage shelter of the car they use a fine-mesh network with a frequent arrangement of camouflage elements, the gap between the car cabin and the camouflage net, and also, the gap between the cab and the body awning is filled with air-mechanical foam with high resistance of the foam array, and the gaps begin to fill with foam mainly about after receiving information about the threat of using fire weapons on a car, and a fire truck is used as a foam generator.

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