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Copyright of Problems of Mechatronics. Armament, Aviation, Safety Engineering / Problemy Mechatroniki. Uzbrojenie, lotnictwo, Inżynieria Bezpieczeństwa is the property of Index Copernicus International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Numerical and experimental investigations of armament systems are an important part of modern design processes. The presented paper reports problems that were encountered on the theoretical analysis of the performance of 35 mm anti-aircraft cannon and the way in which they were solved. The first problem concerns the application of results of closed vessel tests of used propellant in interior ballistics simulations. The use of a nonstandard form of the gas generation rate equation solved this problem. The second problem concerned the assessment of projectile–barrel interaction. The barrel resistance was estimated making use of finite element analysis. The third problem arose from the need to determine the heat transfer from propellant gases to the barrel. The employed formula for the heat exchange coefficient and 2D modelling of the heat conduction in the barrel provided the solution. Selected elements of the theoretical model were validated by shooting range experiments and data provided by the ammunition producer. Using the considered approach, crucial ballistic parameters (maximum propellant gas pressure and muzzle velocity) were estimated with an error of less than 6.0%, without application of additional fitting coefficients. The numerical estimation of the barrel external surface temperature provided a relative discrepancy with the experimental data lower than 6% and enabled the estimation of the critical burst length, equal to 14 shots. [ABSTRACT FROM AUTHOR]

This paper presents studies on perforation and trauma resistance of hybrid soft structures. A selection of hybrid configurations were tested experimentally with a 7.62 × 25 mm Tokarev projectile. Hybrid packages included a wide range of textiles used for personal protection from laminates through plain-woven and multiaxial fabrics to felt. Their effectiveness was evaluated by reference to homogenous packages. The conducted examination demonstrated that hybrid packages employing stiff anti-trauma liners can reduce backface deformation by about 10% compared to homogenous packages. However, too many stiff layers deteriorates perforation resistance by shortening the distance in which a projectile is arrested. Utilization of felt material has a positive effect on trauma and perforation resistance. Soft layers with substantial thickness decrease impulse force and allow projectiles to be stopped over a longer distance. Hybrid packages with felt material have one major drawback in that they are a few times thicker than the other structures tested. An optimal compromise between ballistic performance and thickness is provided by panels based on unidirectional laminates combined with felt and stiff anti-trauma layers. Coupling of plain woven fabric and unidirectional laminate was found to be less efficient than packages entirely made of unidirectional laminate. [ABSTRACT FROM AUTHOR]