Effect of asymmetric nose shape on the cavity and mechanics of projectile during high-speed water entry

Abstract

The characteristics of cavity evolution and motion in water entry created by an asymmetrical nose shape projectile at some different dimensionless excision radius are numerically investigated. CFD numerical methods are used to simulate the high-speed water entry process, the cavitation evolution, flow field and force of the projectile are monitored. The numerical results show that when the projectile enters the water with an asymmetrical nose shape, the cavity bends, and with the increase of dimensionless excision radius, the expansion and contraction speed of cavity increase, and the anticlockwise deflection angle of cavity decreases. The pressure of projectile surface shows an obvious asymmetry, and area of low pressure at the edge of the asymmetric surface is found. Meanwhile, there are two peaks of acceleration while water entry, the deflection of the projectile trajectory is caused by the asymmetric nose shape, and with the increase of dimensionless excision radius, the projectile acceleration decreases, the displacement on y direction increases, and the projectile deflection velocity decrease.