航行体水下连续发射尾涡遭遇与运动干扰特性

In order to study the wake vortex interference and trajectory characteristics of projectiles launched successively underwater at different launching time intervals, based on the Realizable κ-ε turbulence model and energy equation, volume of fluid (VOF) and overlapping grid technology were adopted. Firstly, verification of numerical method and validation of grid independence were presented. The numerical simulation results were in good agreement with the experimental results. Then the numerical simulation method of projectiles launched successively underwater was established. Based on these, the pressure distribution on the side facing the inflow as well as on the backside, trajectory and pitch attitude, particularly the evolution mechanism of vortex in wake flow were studied. The results showed that hairpin vortex-like flow structure was found, multiple hairpin vortex-like flow structures usually exist in a combined form in the flow field region at the tail of the vehicle. The jet event occurred along the inner side of the vortex leg, and the sweep event occurred outside the vortex leg. Meantime, along the inside of the vortex, a low-speed band with a certain streamwise scale was formed. Under the transverse-flow effect, when the surface of the secondary projectile passed through the low-speed strip region of the vortex in the wake, the pressure distribution characteristics of the flow facing side and its opposite side were greatly improved, the stability of trajectory and pitch attitude was increased.