Investigation of high-velocity fragment penetration characteristics and cavity dynamics in a multi-compartment liquid-filled container

The cavity dynamics in liquid-filled containers induced by fragment penetration are central to the hydrodynamic ram effect, which generates intense pressure fluctuations that can cause catastrophic damage to the container. Although multi-compartment designs are widely used in engineering practice, most previous studies have focused on idealized single-compartment configurations. This study investigates high-velocity fragment penetration characteristics and cavity evolution in a multi-compartment liquid-filled container through combined experiments and simulations. A high-speed imaging experimental setup was developed to capture the entire process of cavity dynamics. A fully validated numerical simulation model was established using ANSYS/LS-DYNA to reproduce the fragment’s penetration process, quantify the partitioning of energy transfer among compartments, and simulate a continuous cavity evolution across compartments. The influence of baffles and the fragment’s initial impact velocity on fragment deceleration, energy distribution, and cavity dynamics was analyzed. The results show that the baffles induced localized deceleration of the fragment and altered the flow of the liquid, thereby leading to localized cavity expansion near the baffles. The kinetic energy loss of the fragment was redistributed among compartments in nearly constant proportions (approximately 63% in Compartment I, 24% in II, and 11% in III) and showed limited sensitivity to the initial kinetic energy. Consequently, the cavity collapse occurred asynchronously across compartments. Moreover, the maximum cavity diameter and volume in each compartment increased approximately linearly with the initial kinetic energy. These findings provide useful insight for the safety design and structural assessment of multi-compartment liquid-filled containers subjected to high-velocity fragment impact. • - An Arbitrary Lagrangian-Eulerian (ALE) based method, validated experimentally, was developed to capture uninterrupted cavity growth in a multi-compartment liquid-filled container. • - The first compartment absorbs the majority (∼63%) of the fragment's kinetic energy, guiding targeted anti-penetration design. • - Introduced baffles induce pre-deceleration of the fragment before impact and further cause localized cavity expansion by altering nearby fluid flow. • - Maximum cavity diameter and volume in each compartment scale linearly with the fragment's impact energy.