Abstract:
With the increasing demand of marine military, the realization of continuous and intensive strikes on underwater targets has gradually been paid attention to, and the process often involves problems such as motion interference between multiple bodies and non-constant coupling of cavities, which make the structure and motion characteristics become more complicated. A CFD method is adopted to establish the numerical model of high-speed oblique water entry hydrodynamic characteristics of parallel projectiles. In addition, the calculation results are compared with those of a single projectile to clarify that the flow field distribution and cavities evolution with the axial distance of parallel projectiles. Calculation results show that, compared to the single water entry process, the fluid dynamic characteristics of multiple projectiles in parallel configuration become more complex as the axial spacing decreases. When the axis distance increases to
G = 4, the difference between the hydrodynamic characteristics of the parallel projectiles and a single one is no longer significant. The two cavity contours exhibit good mirror symmetry, and the inner cavities are squeezed close to the projectile surface, and with the increase of axis distance, the interference between the cavities is gradually weakened; high-pressure zone and low-velocity zone mainly exist in the head of the projectile, and there is a phenomenon of high-pressure zones overlap when the axis distance is small; with the axis distance decreasing, the influence of inner cavity pressure and velocity distribution on the cavity evolution is more obvious in the deeper position of the water depth; due to the pressure difference between the inner and outer sides of the projectile surface, the attitude of the projectile changes significantly, which is manifested as the head of the projectile excludes each other, and the tail of the projectile closes together.