Research On Flow Field Structure And Hydrodynamic Characteristics On The Water-exit Process Of Submarine Salvoed Vehicles

In the world background of frequent local wars,underwater launch plays an irreplaceable role in modern warfare because of its unique means of attack,and in order to improve missile penetration capability,salvo underwater technology has become a key research direction.The experiment and simulation research on water-exit process of two underwater salvoed vehicles were carried out under the background of underwater vertical launch.In the experimental research,a launch system with adjustable launch space was set up,And the launch experiment was completed combined with the high-speed camera system.By comparing the cavity shape and trajectory recorded in the launch experiment of single vehicle and double vehicle,the flow field interfere and the resulting changes of the motion characteristics of vehicles in the water-exit process was analyzed.Next,the influence of flow and launch distance on the above parameters was analyzed,and found that the flow will obviously change the cavity shape and trajectory of vehicles,and the decrease of launch space will increase the asymmetry of the secondary vehicle’s cavity,and the offset of the secondary vehicle to the starting vehicle increased.Finally,mechanism analysis of splash form in cavity collapse was analyzed,and it was concluded that the main reason for the difference in the form of collapse is the amplitude of the cavity shock and the gas content,and the cavity collapse will not impact on the surface of the vehicle with sufficient air content and high cavity pressure.In the simulation research,a six degree of freedom motion simulation model of salvo underwater was established,and based on which,the salvo underwater simulation with different launch time intervals was carried out.The pressure field and velocity field under the condition of no launch time interval were analyzed,and the motion characteristic curve of the vehicle and the cause of attitude change was given.Finally,the ballistic and deflection angles of different longitudinal distances of center of mass were compared and analyzed,and the critical longitudinal distance of disappearance of disturbance in the flow field of vehicles was obtained,and the variation rule of the attitude deflection and centroid offset along the longitudinal distance during the launch process was also given.