Dynamical response of liquid-filled thin-walled structure with reinforced tube core wall under hydrodynamic ram impact

• The dynamic full-field displacement history of the rear outer panel of the tube core wall-enhanced liquid-filled thin-walled structure under projectile impact experiments was tested using high-speed camera-based 3D-DIC technology. • The exit wall panel of the structure is designed as a tube core structure, and the dynamic deformation mechanism of a tube core wall-enhanced liquid-filled thin-walled structure under hydrodynamic ram effect is investigated. • The propagation velocities of the pioneer wave and drag wave in the liquid were compared, along with the relationship between the impulse per unit area at different radii of the rear inner panel and the radius. In the event of a projectile impacting a thin-walled enclosure filled with liquid, the moving projectile generates a fluid pulse with high amplitude in the liquid, namely hydrodynamic ram. The rear panel of the thin-walled structure tends to suffer severe damage and failure under the action of HRAM. For the purpose of boosting the HRAM resistance performance of liquid-containing thin-walled structures, a novel configuration with reinforced tube core walls is proposed herein. Concurrently, ballistic impact experiments and finite element simulations were carried out to investigate the dynamic response mechanism and energy absorption characteristics of this reinforced structure. Investigations show that the pioneer wave in the liquid propagates faster than the drag wave. Taking the projectile’s exit point as the origin, the impulse per unit area exerted on various radial locations of the rear inner panel exhibits a negative exponential relationship with the radius. The tube core wall consists of a rear outer panel, tube core, and rear inner panel, with distinct deformation modes: the outer panel exhibits overall bulging and petal-shaped rupture; the tube core shows overall bending, circular rupture, and local buckling around ruptures; the inner panel displays overall bulging and circular rupture. In energy absorption, the tube core dominates at 53.93% of the wall’s total, followed by the outer panel (30.52%) and inner panel (15.56%). This distribution effectively inhibits inner panel deformation and damage, providing theoretical support for the design of hydrodynamic ram-resistant liquid-filled thin-walled structures.