Aspect ratio-dependent fragmentation and debris cloud evolution in hypervelocity impact of cylindrical projectiles

This paper investigates the aspect ratio effect on the fragmentation characteristics of cylindrical projectiles during hypervelocity impact with a flat plate, and analyzes the mechanisms based on unloading patterns. Using the smoothed particle hydrodynamics method, the debris clouds generated after the impact of cylindrical projectiles with various aspect ratios (0.05–6.05) on the plate were simulated. The energy mapping method was applied to quantitatively characterize the radial energy distributions of the debris clouds. The study explores how the aspect ratio influences fragmentation characteristics and the energy distribution of debris clouds. Based on the variation trend of the energy concentration degree of the debris cloud with the aspect ratio, five characteristic intervals of the aspect ratio were defined. To reveal the generation mechanism of these characteristic intervals, this study correlates the propagation and unloading process of shock waves within the projectile with the energy concentration degree of the debris cloud. The identified characteristic intervals and their correlation with shock wave unloading patterns establish a link between projectile geometry and debris cloud energy distributions.