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An analytical-experimental method has been used to investigate the penetrative capability of cylindrical VNZh-90 and VNZhK + 75% VK8 with flat heads and conical noses in interaction with a steel barrier in the velocity range of 1200–1300 m/s. Calculation results are presented for interaction of the considered strikers with steel barriers at impact velocities of up to 2000 m/s. [ABSTRACT FROM AUTHOR]

An experimental-theoretical assessment has been made of the minimum required velocity for through penetration of 20–60 mm thick steel barriers by a supercavitating VNZR-95 alloy striker. Parametric calculations have been conducted within the framework of an elastic-perfect plastic Prandtl–Reuss model. [ABSTRACT FROM AUTHOR]

A mathematical model has been constructed and verified for the behavior of a composite barrier under the conditions of shock-wave loading. An analytical-experimental method has been used to assess the effects of a modified composite barrier in high-velocity interaction with a spherical steel striker in the velocity range of 500–1200 m/s. [ABSTRACT FROM AUTHOR]

High-temperate vacuum sintering has been used to obtain porous composite tungsten carbide alloy TNIC (W–Ni–Fe–Co) + 69 wt.% WC. The results of investigations into the microstructure and physical-mechanical properties of the alloy are presented. An experimental investigation has been conducted into the high-velocity interaction of cylindrical strikers made of this material with steel plates in the velocity range of 1200–1400 m/s. [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]

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]

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]

Experimental-theoretical investigations have been conducted into underwater supercavitating motion of cone strikers from various materials in a broad range of velocities. An estimate of the range of strikers' velocities has been performed for the implementation of their nondestructive entry into water and motion in it in a supercavitating regime. A possibility of an accurate hit by supercavitating strikers on underwater barriers in a supersonic range of motion velocities has been shown. [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]

This article presents the results of external ballistic investigations of motion in the air of supercavitating strikers cannon-launched in a group, and a gas-dynamical picture of flow past two strikers in the chamber of an aerodynamic installation. Mathematical simulation of the process of flow past two strikers has been carried out, and their aerodynamic coefficients have been calculated. The conditions for cannon-launching of a group of supercavitating strikers have been determined that provide for their motion along the aerodynamic portion of the route and their subsequent entry into water with an angle between the longitudinal axes of strikers, at which their motion is stable. [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]

Results of a complex experiment-calculated investigation of the structure of a nonstationary gas flow in the working path of a hypersonic ramjet engine are presented. Methods of experimental determining the pressure and temperature distributions over the wall of an axisymmetric channel of complex geometry with a sudden widening are proposed and described. The problem on the gas flow over a ramjet engine positioned in a wind tunnel was solved. [ABSTRACT FROM AUTHOR]

An experimental procedure has been developed to record phenomena in impact destruction of a container with a fluid. The phenomena were recorded using x-ray pulse devices and a high-speed filming technique. The propagation of compression waves in the fluid was registered using bubble-markers in the form of air curtains in the fluid mass. The pressure in the compression wave was measured by a gallium arsenide crystal-based sensor. An investigation has been made into the characteristics of the phenomena occurring during the destruction of a container with a fluid by a high-speed striker. We have established the dependences of cavity development in the fluid, the striker motion law, the time dependence of pressure, and the pressure attenuation in the fluid. The obtained dependences make it possible to establish objective physical data on phenomena in impact-stressed containers and to solve the issue of strength of a container with a fluid. [ABSTRACT FROM AUTHOR]

The investigation is devoted to an experimental and theoretical research into the high-velocity motion of a group of supercavitating kinetic strikers in water. An experimental launching technique has been developed, and investigations have been conducted into the high-velocity motion of a group of supercavitating strikers on a hydroballistic testing facility, and a calculation procedure has been developed for modeling possible deviations of the strikers′ motion in water in a group start. Experimental data have been obtained on the motion of one and two supercavitating strikers on the initial portion of the path at velocities of the order of 1200 m/s, which serve as initial conditions for identifying the strikers' deviation from the target at a distance of up to 100 m. [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]

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]

The paper is devoted to the investigation of the high-velocity motion of supercavitating kinetic strikers in water with account of the intraballistic processes in the powder chamber and outside the channel cut of the ballistic installation, the supercavity dynamics, and also the interaction of the strikers with underwater barriers (obstacles). The process of supercavitating motion at underwater start is modeled on the basis of solving Reynolds-averaged Navier–Stokes equations with turbulence equations and cavitation equations for a multiphase medium. To investigate the stressstrain state and a possible destruction of solid bodies in interacting with underwater barriers of various types, mathematical modeling is conducted on the basis of an elastoplastic model of a medium. The range of investigated velocities is 50–850 m/s. [ABSTRACT FROM AUTHOR]

Consideration is given to conditions ensuring stable high-velocity motion of supercavitating kinetic strikers in water. To investigate the stressed-strained state and a possible destruction of solid bodies during the motion in water and in interaction with underwater barriers of various types, the authors carry out mathematical modeling based on a unified methodological approach of the continuum mechanics. The range of the velocities under study is 500-1590 m/s. Results of the group start of supercavitating strikers are given. [ABSTRACT FROM AUTHOR]