Effect of Material Density on the Tail-slapping Characteristics ofSupercavitating Projectiles

Abstract

Generally, the tail-slapping motion of underwater supercavitating projectiles has a significant impact on their ballistic stability and operational performance. In this study, a numerical model of such supercavitating projectiles integrating a dynamic mesh is established to investigate the impacts of the tail-slapping characteristics of supercavitating projectiles under different material densities. Moreover, the ballistic and hydrodynamic characteristics of projectiles using aluminum alloys, structural steels, and tungsten alloys are scrutinized. Consequently, the attack angle, pitch angular velocity, and hydrodynamic coefficient of the tail-slapping motion of the projectile are found to demonstrate periodic changes with the material density under a given export kinetic energy. Additionally, the greater the material density, the longer the period of tail slapping; the slower the speed decay, the smaller the impact on the vertical speed of the projectile. Interestingly, the structural steel projectile demonstrates the best ballistic performance among the three candidate materials.

Keywords

• supercavitating projectile
• material density
• tail-slapping motion
• hydrodynamic characteristics