Analysis of the combined impulse of fragments and the shock wave composite load

Abstract

This study conducted experiments and numerical simulations to investigate the Mechanical Properties of Fragments and Shock Waves generated blast. A combined impulse calculation model was established through the study of post-explosion motion patterns and impact load characteristics of fragments and shock waves acting on targets.The rationality of a combined impulse calculation model ed using a sled test.Numerical model of square plates subjected to blast loading was established by LS-DYNA to analyze the influence of composite loads with different cased charges on a square plate at different standoff distances.The variation laws of the combined impulse under different standoff distances and different charge structures were obtained.Results indicated that the combined impulse exhibited an exponential decrease with standoff distance in the near-field region of the explosion.The impact acting on the target was characterized by perforation and deflection.The impulse acting on deflection and penetration due to the inertial effect of the target, energy absorption effect, was approximately 15.6 % lower than the combined impulse at the beginning of the blast,the attenuation increases with the increase of distance.The length-to-diameter ratio of cased charges, the more the charge mass,the greater the combined impulse of the resulting multiple loads.With the same length-to-diameter ratio, increase the charge mass,the use of small-sized fragments or high-energy charges had an enhanced effect on the combined impulse.