Study on the mechanism of water entry under the effect of floating ice based on a penalty function-based fluid–structure interaction method

Abstract

Water entry in polar regions is a hot topic of mechanical dynamics. Nonetheless, the presence of floating ice can significantly influence the water entry process. In this paper, a novel two-way fluid–structure interaction (FSI) scheme based on the penalty function is proposed that is suitable for collision between objects into the water. In this scheme, the collision between the projectile and the floating ice is solved by the penalty function, and then, the collision information is transmitted to the fluid solver to solve the passive water entry process. Using dynamic models and experimental data, the accuracy of the new FSI scheme is validated. The cavity evolution and dynamic response of the floating ice colliding with the projectile are studied. During passive water entry, the development of the splash crown is inhibited. The contact line at the floating ice exhibits different movement states under different mass ratios (M). Subsequently, the passive water entry of eccentric collisions is studied, and the influence of eccentricity (Liz*) is considered. Different collision modes and contact-sliding modes occur between the floating ice and the projectile during the eccentric collision. The evolution of the cavity also appears to have asymmetric characteristics. The horizontal displacement of the floating ice influences the transition of the collision mode under the same wetted area.