Spatial distribution and damage prediction of explosive fragments in cylindrical shells

Fragmentation analysis in explosively driven cylindrical shells is crucial for weapon development and structural protection. To evaluate the overall response of protective structures to explosive fragments, it is essential to clarify the spatial distribution characteristics of the fragments. This study investigates the influence of fracture mode on fragment morphology and spatial distribution through numerical simulations, highlighting the non-uniform fragment distribution. A damage analysis method based on the kinetic energy of fragments is proposed, which illustrates both the spatial distribution and energy concentration in specific areas. The results reveal that the kinetic energy distribution of fragments exhibits a clustering effect only in shear fracture, corresponding to the elongated fragments generated from the middle of the cylindrical shell. Furthermore, a theoretical model is developed to determine the maximum kinetic energy angle, facilitating the rapid identification of severely damaged regions in protective structures. The experimental results validate the non-uniform distribution of perforation areas on witness plates and demonstrate that the theoretical model can accurately predict the location and extent of severe damage under varying conditions. This study provides an energy-based theoretical framework for damage assessment of explosive fragments, offering valuable insights for damage and protection design in fields such as the ship damage evaluation and the blast resistance of concrete structures.