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For testing anti-meteoroidal protection of spacecraft, it is proposed to use charges that form compact elemants of variable shape. Shape charges, their construction, and the process of functioning are considered. During the operation of such a charge, the explosive throws the metal liner at a distance of several hundred charge diameters. The metal liner is deformed in motion and takes a compact shape. In this case, copper liner of variable thickness were used, the outer and inner surfaces of which are formed by a combination of spherical surfaces. A plane-wave generator with a variable angle of inclination of the detonation wave is considered as an initiation system in the charge. The results of mathematical modeling of the functioning of charges, which determines the effect of charge parameters on the effectiveness of the action, are presented. The efficiency of the charges was determined by the parameters of the compact element - its shape and speed. The paper also evaluated the influence of the angle of inclination of the plane-wave generator on the shape of the element. The dependences of the speed of the element and its elongation on the angle of inclination of the converging detonation wave are obtained. It was found that when the angle of inclination of the converging detonation wave front decreases, the elongation and speed of the compact element increase.

In this paper, we present the results of numerical simulation of explosive formation of a high-speed compact element from copper, steel, and aluminum cumulative liners combining the shape of a hemispherical segment smoothly converting into a cylindrical surface (“hemisphere–cylinder” liners). The problem is solved in a two-dimensional axisymmetric setting considering the limiting parameters of the dynamic stress-strain state causing plastic flow and destruction of the cumulative liner material. The original model of the functioning of cumulative shaped charge, which determines the effect of individual elements of the cumulative liners, including the difference in numerical characteristics of their physicomechanical properties and critical destruction conditions, on the final parameters of the high-speed compact element, was used. The plastic properties of the material and the critical conditions for its destruction were found not to affect the final velocity of the formed high-speed compact element, but they affect its shape, dimensions, and mass.

We consider the physicomathematical formulation of the problem of explosive formation of a penetrator from a low-sphericity copper lining. Calculations are made for the formation of a penetrator for a phlegmatized hexogen charge for two models of the behavior of the lining material (copper), and the results are compared with the experimental data.

For ground-based simulation of the penetration of particles and elements into the body of the spacecraft, it is proposed to use charges that form high-speed elongated aircraft (HSEA) with a variable form. In the course of the operation of such a charge, an explosive agent throws a metal liner for a distance of several hundred charge diameters. The metal segment liner is deformed in the process of throwing and takes the shape of an elongated aircraft. Steel cladding with a degressive and progressive profile was used, the outer and inner surfaces of which are formed by spherical surfaces, as well as a combination of spherical and conical surfaces. The results of the numerical analysis, which determines the influence of the geometrical and physicomechanical parameters of segment cumulative liners (CL), on the effectiveness of the action of the charges that form high-speed elongated aircrafts are presented. The effectiveness of the charges was determined by the characteristics of the formed aircraft — elongation, degree of fullness, and diameter of the tail plane (skirt). Dependencies describing the influence of the of the liner material and the radius of transition of a spherical surface into a conical surface on the elongation of the aircraft and the diameter of the skirt are established. The possible contradictory effect of a transition in the radius of transition of a spherical liners surface into a conical surface on the parameters of the aerodynamic stability of a high-speed elongated aircraft is shown.For ground-based simulation of the penetration of particles and elements into the body of the spacecraft, it is proposed to use charges that form high-speed elongated aircraft (HSEA) with a variable form. In the course of the operation of such a charge, an explosive agent throws a metal liner for a distance of several hundred charge diameters. The metal segment liner is deformed in the process of throwing and takes the shape of an elongated aircraft. Steel cladding with a degressive and progressive profile was used, the outer and inner surfaces of which are formed by spherical surfaces, as well as a combination of spherical and conical surfaces. The results of the numerical analysis, which determines the influence of the geometrical and physicomechanical parameters of segment cumulative liners (CL), on the effectiveness of the action of the charges that form high-speed elongated aircrafts are presented. The effectiveness of the charges was determined by the characteristics of the formed aircraft — elongat...

The physicomathematical problem of the explosive formation of a cumulative knife (jet) from a cumulative charge and its penetration into a 250-mm-thick armed concrete obstacle is considered. Numerical simulation data for a specific extended cumulative charge acting against this obstacle at different focal lengths of the charge are presented.

The shock stage in the behavior of explosively loaded steel plates and cylindrical shells was studied experimentally. A three-wave structure of the shock front was observed for both plane and cylindrical samples. The split-off strength of the shell and plate materials was determined. For both loading schemes, the split-off was shown to not occur for the samples with a thickness of 1 mm. The decay of the pressure amplitude in the first shock wave was found to be appreciably stronger for the cylindrical samples than for the plane samples.

The equation of state was developed for materials subjected to the polymorphic transformation upon explosive loading with an explosive charge. The formula obtained was used in the numerical modeling of the explosive projection of plates and cylindrical shells fabricated from St 20 steel. The theoretically estimated kinematic parameters of a projected body were compared with the experimental data.

The effect of preheating of liners on the penetration capability of shaped charges is considered theoretically. It is shown that for a plastically fractured shaped‐charge jet, preheating of the liner generally increases the effective jet length and shaped‐charge jet penetration. Restrictions on the parameters of preheating of shaped‐charge liners due to the possible thermal initiation of the explosive are established. It is noted that excessive weakening of a shaped‐charge jet can lead to transition from plastic to volume fracture with a corresponding decrease in shaped‐charge jet penetration. The ultimate possibilities of the thermal method for increasing the penetration capability of shaped charges are estimated. Calculation results are compared with available experimental data.