高速旋转射弹波浪入水多相流场与弹道特征数值仿真研究

Based on the overlapping grid technique and a 6DOF algorithm, numerical simulation of the water entry process of a high-speed pinning projectile in waves was carried out. The cavitation shape, trajectory characteristics, and hydrodynamic load characteristics of the projectile at different positions of wave surface, such as wave crest, wave node 1, wave trough and wave node 2, were analyzed. The results show that the projectile body experiences water impact, cavitation formation, supercavitating, and wetting under four cases, among which the tail of wave node 2 collides with the cavitation first, and the tail of wave node 1 collides with the cavitation last. At the end of the simulation, the lateral displacement and velocity change from large to small are: wave node 2, wave crest, wave trough, and wave node 1. In the initial stage of the four cases, the force and moment coefficients magnitude of the projectile sailing in the cavity are small. In the later stage of water entry, the surface of the projectile is wet in a large area. The force and moment coefficients under different cases are quite different. The nominal entry-water angle is 25° and the same under the four cases, but due to the existence of wave surface, the actual entry-water angle of the projectile changes. The effective entry-water angle of the projectile from small to large are: wave node 2, wave crest, wave trough, and wave node 1, and the values are: 10.309 4°, 25.003 2°, 25.009 8° and 39.662 0° respectively.