Influences of floating ice on the vertical water entry process of a trans-media projectile at high speeds

It is of great significance to study the hydrodynamic process of trans-media projectiles passing through ice-water mixture at high speeds for the application of weapons in low-temperature environments of high-latitude water areas during the winter. Based on the volume of fluid (VOF) method and the Schnerr-Sauer cavitation model, the processes of a projectile vertically entering water (without floating ice) and passing through ice-water mixture without collision with ice at different initial high speeds were studied. The influences caused by the ice on the cavity evolution, flow field characteristics, hydrodynamic and ballistic characteristics were analyzed. The results showed that the floating ice alters the volume of air that is sucked into the cavity by hindering the diffusion and contraction movement of the liquid at the gas-liquid interface, changing the degree of cavitation and the formation and development modes of the cavity. It causes a different evolution of the cavity shape, delays the cavity closure, and affects the hydrodynamic force and ballistic characteristics of the projectile ultimately. With increasing velocity, the influence of ice on cavity shape reduces, however, on projectile ballistics, it enhances. The results can provide some theoretical references for further application research on trans-media weapons in floating ice environments.