Numerical study on the high-speed water-entry of hemispherical and ogival projectiles

Abstract

The water entry problem is considered as a classic problem which has a long research history; however, projectile water entry is still a difficult problem that has not been completely solved. In this paper, the effects of the projectile nose shape on laws of velocity attenuations for all projectiles were studied by a series of numerical simulations using the AUTODYN-2D. The result showed that the drag coefficient increases monotonically with the initial velocities for an identical projectile and decreases with the CRH values for projectiles at the same velocity. A simple and effective model was proposed to determine the relations between the drag coefficients, nose shape coefficient and initial velocities of projectiles. © 2012 American Institute of Physics.