Investigation of dynamic response characteristics of spherical shells subject to forward underwater pulse loads

This paper explores the dynamic response of spherical shells subjected to intensive underwater shock waves. Both experimental tests and numerical simulations are performed to analyze the relationships between the target deformation mechanism and the load or geometries, including the underwater-shock intensity, thickness, and curvature. The results show that the fluid-structure numerical model accurately simulates the impact response, and that the errors between the simulation and experiments are less than 7%. Investigations also reveal that the deformation behavior of spherical shells is primarily influenced by the shock wave intensity and the curvature radius. The target deflections are decreased by 35.4% when doubling the shell's thickness. Furthermore, reducing the radius of curvature by 50% leads to a 40.42% increment in the final deflection. The static pressure imposed on the shell significantly accelerates the deformation process, and leading to greater deflection. The results can provide insights for designing impact-resistant spherical shells in ocean structures.