No abstract

Analyses presented in the article were carried out in order to characterize the main parameters of the shaped charge jet formed due to detonation of the PG-7VM warhead. As opposed to the previously published studies in which rolled homogeneous armored steel was mainly used as a target, in the current work the warhead penetration capability was determined against more contemporary high-hardness (500 HB) ARMSTAL 30PM steel armor with precisely determined mechanical properties. The research included experimental depth of penetration tests and their numerical reproduction in the LS-Dyna software. Special attention was paid to factors that could perturbate the shaped charge jet formation process and under- or overestimate its penetration capability. For this reason, warheads were X-ray inspected for structural discrepancies (voids or air inclusions in explosive, misalignment between the body, explosive, and liner, or lack of contact between the explosive and the liner) and properties of materials (explosive, targets, and most important warhead components) were analyzed before the experiments. The numerical model of the warhead was defined more accurately than in previously published studies, since it was based on the real grenade dimensions and its technical documentation. Thanks to this, the depth of penetration of the target made of ARMSTAL 30PM armored steel plates by the shaped charge jet formed from the PG-7VM warhead obtained by numerical simulation was consistent with the experimental results and equaled 278 mm and 280 mm, respectively. The difference between the experimental and numerical value was smaller than 1%, which confirms that the developed methodology of modeling allows users to properly reproduce the PG-7VM shaped charge jet formation and target penetration processes. A verified numerical model of the shaped charge jet penetration into a steel target was used to determine depth of penetration in function of stand-off distance for the PG-7VM warhead. A maximum depth of penetration of about 317 mm was obtained for the stand-off distance of 360 mm, which may indicate the potential direction of modernization of warheads.

No abstract

No abstract

Investigation using Real-Time X-ray Radioscopy (RTR) of the combustion processes occurring in two different configurations of pyrotechnic items, currently used in ordnance in service with the Polish Armed Forces, are presented. In the first configuration, employed in the delay elements of the RGM type of impact artillery fuses, the end-burning delay pyrotechnic column in its narrower part ended with cavity, is situated in front of the inlet of the axial channel of the output tubular pyrotechnic augmenting charge. In the second configuration, utilized in tracers of anti-tank guided missiles, the end-burning pyrotechnic charge with an ignition cavity is inserted into the steel body and closed hermetically at both ends by plastic discs. In each configuration, ignition of the tested item was initiated by an electric fusehead system. The RTR sequence of images (30 fps) of the combustion of the tested items showed that the burning surface of their pyrotechnic charges were distinguished as a boundary between the unburnt part of the pyrotechnic charge and its distinctly less dense combustion products. For selected time points in the combustion process, the shape and position of such boundaries were captured. From these data, it was possible to discover more about the combustion phenomena occurring in these tested items, including the evolution and movement of the burning surface.The combustion processes of the tested pyrotechnic delay elements and tracers, were occurring in accordance with the intended (expected) scenarios, i.e. all of the pyrotechnic charges were successively and totally consumed, and during their combustion there were no premature effects resulting in a shortening of their burning time.