Numerical simulation for high speed oblique water entry of different density projectiles

Abstract

To explore the effects of material density on the cavitation flow field of a projectile entering water at an oblique angle at 300m/s, numerical simulations were conducted. The model was based on the finite volume method, VOF (Volume Of Fluid) multiphase model, Schnerr-Sauer cavity model, SST(Shear Stress Transfer) k-ω turbulence model and dynamic mesh method. The evolution laws of cavity shape, motion characteristics and hydrodynamic characteristics of water entry are analyzed. The research results show that the numerical calculation method can effectively simulate the change of cavity shape during the water entry of the projectile. The larger the density is, the smaller the diameter of the cavity formed after entering water is; the longer the cavity is, and the smaller the diameter of the cavity opening is; The peak value of pressure on the surface of projectile with different density is the same at the moment of entering water, but the projectile with larger density experiences a slower rate of the surface pressure decline; Moreover, the larger the density, the smaller the acceleration peak value of the projectile at the moment of entering the water, the slower the velocity decay after entering the water, and the deeper underwater at the same time.