Study On Fluid-Solid Coupling Mechanism Of Water Entry

When the vehicle crosses the medium at high speed,it will arouse the flow of the medium near the head of the vehicle.Due to the violent reaction force exerted by the fluid medium on the vehicle,the vehicle will experience the huge transient impact load of the fluid medium in the first few milliseconds.Under such violent impact load,the dynamic response of the structure will occur.If the strength of the structure is insufficient,it will cause elastoplastic deformation of the structure,and even cause the structure to break,buckle and break.The impact of the trajectory of the trajectory of the vehicle caused problems such as leaping and diving.Therefore,how to safely and reliably realize the vehicle cross the medium is a great significance in the field of cross-media research.In this paper,the arbitrary Lagrangian Euler method(ALE)is used to establish a numerical model of the high-speed trans-medium medium of vehicle The impact load characteristics,cavitation evolution rules and load reduction mechanism involved in the process of navigating the body across the water and air medium are studied and analyzed.The motion response characteristics and environmental impact mechanism of the trans-media medium are revealed,which provides a reference for the design and manufacture of high-speed trans-media medium bodies.Firstly,based on the dynamic characteristics of the high-speed trans-media medium of the follower body,the ALE method was selected to establish a numerical model of the cross-media kinematics of the body,and the mechanism research was carried out to verify the convergence and correctness of the ALE method.The effects of the compressibility of the flow field and the elastoplasticity of the structure on the impact load and cavitation evolution of the vehicle across water and air are analyzed.Based on this,in view of the problem of trans-medium trajectory and cavitation evolution,six types of bullets mainly studied in the article are designed by analyzing the existing missile configuration.The ALE method is used to simulate the free surface,cavitation evolution,and pressure in the cavities of the projectile across water and air,to verify that the ALE method is feasible for the simulation of the trajectory and cavitation evolution of the projectile across the medium.Sex and accuracy.Based on this,the effects of parameters such as the center of gravity of the projectile,the aspect ratio of the projectile,and the angle of attack on the water on the characteristics of the ballistic cavities were analyzed.Aiming at the study of the load characteristics of the high-speed trans-medium medium of the vehicle,the ALE method was first used to simulate the water entry process of the flat-head supercavity projectile,ball head and olive projectile.The simulation results were compared with the experimental conclusions.Accuracy of load calculation for ingress problems.The effects of parameters such as the head shape,water velocity,and water angle on the load were studied and analyzed,and the influence of various parameters on the impact load was obtained.Based on the actual water inflow problem,there are unavoidable disadvantages such as high speed of the voyage body and a certain angle of attack before entering the water.From the two aspects of the missile body configuration and the motion parameters,the anti-shock configuration of the high-speed air-water medium is studied mechanism.