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A promising direction in barrel ballistics aimed at increasing the muzzle velocity of a projectile is the use of new propellants as an attached charge. This paper presents an experimental and theoretical method for determining the law of propellant combustion in a manometric experiment (in a closed volume). Within the framework of this method, a small number of experiments could be sufficient to determine a change in the law of combustion during the propellant burnout and depending on pressure. This method is demonstrated on the example of processing three experiments with model high-density propellant. The laws of combustion of high-density propellants, obtained in this study, can later be used to calculate the gas-dynamic parameters of a shot from a barrel system or a nozzle bomb (in a semi-closed volume) using these propellants. [ABSTRACT FROM AUTHOR]

The combustion of a model high-density propellant (MHP) under the conditions of a closed volume has been investigated. A description is given of the main components and mechanisms of the manometric bomb being used. Procedures are described for determining the laws of propellant combustion in a manometric experiment, and a comparison is made of computational-experimental data. The distinctive features of the formation of an MHP combustion surface in various containers have been identified and described. The dependences of the layer combustion velocity of two model high-density propellants on pressure have been determined. [ABSTRACT FROM AUTHOR]

An experimental and theoretical study of the combustion of granulated charges consisting of pyroxylin powders in a manometric bomb of constant volume is presented. A comparison was made of the experimentally measured dependence of pressure increase in a manometric bomb with calculations according to thermodynamic model of combustion of a gunpowder sample in a manometric bomb using the empirical law of the dependence of the burning rate on pressure and a conjugate model of unsteady combustion of gunpowder. The unsteady rate of burning of pyroxylin powder, due to the high rate of pressure growth in the manometric bomb, differs from the quasi-stationary speed. This difference depends on the rate of pressure growth and on its absolute value and decreases with increasing pressure. [ABSTRACT FROM AUTHOR]

Abstract—The analysis of supercavities formed during the high-speed motion in water of two closely spaced supercavitating strikers is performed. By comparing geometric characteristics of supercavities, the possibility of qualitative assessment of influence degree of closely spaced strikers on each other is shown. By the example of two strikers, the characteristic distance between them was determined, at which the minimum mutual influence of the strikers on each other is observed. [ABSTRACT FROM AUTHOR]

Results have been presented of intraballistic design work aimed at identifying the main characteristics of a small caliber laboratory launcher and the composition of the propellant charge for various striker masses. Technical solutions have been obtained for sabots of supercavitating strikers accelerated in a small size laboratory ballistic installation. The level of the pressure acting on the striker, as it enters the water directly from the barrel of the installation, has been determined. Travel path ranges have been calculated for supercavitating strikers accelerated in a small size laboratory ballistic installation. [ABSTRACT FROM AUTHOR]

On the basis of ballistic design, an assessment of the dimensions of the launcher with an accelerating channel length of 20 cm was made. The hydroballistic stand was adapted for testing small-sized launchers. With the use of a small-sized projectile installation, the modes of entering the water of strikers through the air section and directly from the accelerating channel are implemented. [ABSTRACT FROM AUTHOR]

The interaction of supercavitating strikers with obstacles placed in water was investigated in a wide range of intersection angles. Several options of the interaction of strikers with obstacles are considered, including through puncturing, destruction of the striker, and ricochet. Estimation was made of the magnitude of the decrease in the speed of strikers in the cases of through puncturing and ricochet. [ABSTRACT FROM AUTHOR]

A mathematical model has been constructed for the behavior of a tungsten carbide alloy on the basis of TC8 (tungsten carbide, 92%; cobalt, 8%) and WNFC (W–Ni–Fe–Co), or TNIC (tungsten, nickel, iron, and cobalt), in conditions of shock-wave loading. A scheme has been suggested for the process of mass loss and self-sharpening of the striker in dynamic interaction with the target. The computational-experimental method has been used to investigate the capacity of cylindrical strikers made of this composite to penetrate into a steel target at an impact velocity of 1260 m/s with account for the dependence of yield stress on the intensity of plastic deformation considering both the stage of strengthening and the stage of its structural softening in the process of deformation. [ABSTRACT FROM AUTHOR]

Results are presented of an experimental-theoretical investigation of the motion in water of supercavitating strikers made of steel and aluminum and tungsten (TNI, i.e., tungsten, nickel, and iron) alloys in a broad velocity range. Estimates have been made of the ranges of velocities of entry into water in which the investigated supercavitating strikers from various materials are not destroyed and preserve the original shape. Experimental and computational data have been obtained on the value of deviation of the trajectories of two simultaneously starting from each other supercavitating strikers at the initial stage of their group motion in water depending on the materials they are made of. [ABSTRACT FROM AUTHOR]

Analysis has been made of the ballistic characteristics of the shots, and a powder grade has been indentified for a propellant powder charge ensuring the lowest level of force action on the projectile assembly including a group of supercavitating strikers in a gun-start. [ABSTRACT FROM AUTHOR]

The paper presents the methodology elaboration for the investigation of a high-speed impact interaction between the projectile and a split target. The impact interaction speed ranges between 1500 and 2500 m/s. The split target consisting of a polymethyl methacrylate target and a witness target made of D16 aluminum alloy, is placed at a 60 mm distance from the latter. Using mathematical simulation, all effects that occur during the high-speed impact interaction, are analyzed more precisely. [ABSTRACT FROM AUTHOR]

Using the computer-based simulation method within the scope of continuous mechanics, impact interaction with a speed of 3000 m/s between a steel ball and a transparent armor target is calculated (the target has three layers). The face layer of the transparent armor is made of aluminum oxynitride; the middle layer, of hardened glass; and the lower layer, of polycarbonate. The influence of the angle of the projectile approach to the target and thickness of the hardened glass layer on the process of target penetration is studied. [ABSTRACT FROM AUTHOR]

Using high-temperature sintering, tungsten-carbide alloy-based specimens with improved functional properties have been explored. The penetrative capability of strikers fabricated of these samples into a steel barrier at an interaction speed of 1300 m/s has been investigated in comparison with that of the mass and size of a VNZh-90 alloy-based analogue. [ABSTRACT FROM AUTHOR]

We propose a series of experiments aimed at analysis of peculiarities and revealing general regularities in the penetrability of strikers made of a composite material based on tungsten + nickel + iron + cobalt alloy with an admixture of highly rigid refractory titanium–tungsten carbide particles in various initial conditions. In particular, we have analyzed the effect of the initial temperature of the striker in the interval from –50 to 50°C on the penetration into a steel obstacle experimentally and by calculations. It is found that the initial temperature of the striker does not noticeably affect the penetration depth in the obstacle at impact velocities up to 2500 m/s. The penetrability is found to be 20% higher than that for a monolithic massive analog made of VNZh-90 alloy. [ABSTRACT FROM AUTHOR]

On the basis of an experimental and theoretical approach, the authors have considered an algorithm for modeling the behavior of advanced propellants in barreled systems of varying caliber. The proposed algorithm makes it possible to conduct preliminary investigations into the possibility of using advanced fast-burning propellants in the existing barreled systems and in advanced systems of varying calibers and for various purposes. A possible increment in the muzzle velocity of a projectile due to the advanced propellants added to the propellant powder charge is assessed without full-scale testing. [ABSTRACT FROM AUTHOR]

In this study, we perform calculations and experimental studies of the destruction of composite impactors from a porous tungsten–nickel–iron–cobalt alloy with 10 wt % tungsten titanium carbide at high-speed impact with steel barriers. In ballistic tests over a wide range of velocities, there is a significant excess of the penetration depth of these impactors into steel barriers compared to the mass-dimensional analog of a tungsten–nickel–iron alloy with 90% tungsten content. Based on the analysis of crater morphology and the structure of impactor fragments after introduction into the obstacle, we assume that the impactor is "self-sharpened" by localizing plastic deformation, which reduces the effective interaction area and increases the penetration depth. To describe the destruction, we modified the mathematical model of a porous ideal elastic-plastic body with a complex structure with the possibility of considering the adiabatic shear mechanism during interaction between the impactor and the obstacle. [ABSTRACT FROM AUTHOR]

A mathematical model of a shot from a smoothbore ballistic installation for a gun start of a group of supercavitating strikers has been developed. To verify the mathematical model, experimental investigations into high-velocity launching of a group of bodies on a hydroballistic testing facility have been conducted. A comprehensive parametric investigation has been conducted to determine conditions for loading the ballistic installation to achieve the required muzzle velocity, ensuring a supercavitating regime of motion for a group of strikers in water. [ABSTRACT FROM AUTHOR]

Peculiarities of the motion of one and two supercavitating strikers in water upon their simultaneous entry into water at speeds exceeding the speed of sound in the medium are considered. Conditions have been developed to ensure nondestructive entry of strikers into the water and stable movement along an aiming trajectory in the transonic speed range. A stable joint motion of two strikers in water at supersonic speed is obtained. [ABSTRACT FROM AUTHOR]