Three-Phase Coupling Numerical Simulation of Underwater Penetration of Supercavitating Projectile into Target Plate

The essence of supercavitating projectile penetration is the dynamic response of a special underwater structure subjected to high-speed impact load. In this paper, the damage effect of 12.7 mm supercavitating projectile penetrating typical underwater target shell is studied. Based on LS-DYNA finite element analysis software, the equivalent model of supercavitating projectile penetrating into curved surface target vertically in water environment is established. The combined damage effect of kinetic energy penetration and bubble collapse on target plate during penetration is simulated, and the stress variation and structural deformation law of target plate at different stages are obtained. The results show that the peak pressure of water medium on the head surface reaches 768 N when the velocity of projectile is 200 m/s before penetrating the target, and the surface of the target exhibits obvious concave deformation; with projectile kinetic energy penetration and bubble collapse impact during penetrating process, the impact effect of water medium is less than 2% of that by kinetic energy penetration. After penetrating the target, a water jet with a peak velocity of 42 m/s is formed on the front of the target and further acts on the break. The overall bending deformation of the target plate occurs. In the range of 200 m/s to 300 m/s, the bending deformation decreases with the increase of projectile impact velocity. Ductile perforation occurs locally on the target plate, and the projectile has better perforation effect in water environment. The change of projectile velocity has little effect on the size of the perforation.