Analysis Of High Speed Projectile Water-Entry Process Based On Fluid-Solid Coupling Simulation

The development of ocean engineering and aerospace engineering has put forward higher requirements for the study of cross-medium motion.Water-entry impact is the most common and most widely used cross-medium problem.The progress of fluid-solid coupling methods has promoted the study of water-entry impact.The numerical analysis method is used to analyze the high-speed waterentry projectiles with various shape,which promotes the actual projectile development.In this research,the ALE numerical analysis method based on the penalty function is used to carry out a study on the high-speed water-entry impact process of a special kind of projectile.The load response mechanism of the slender projectile during high-speed water-entry impact is obtained,and the effects of speed,angle,head rudder deviation,and counterweight position during the impact are summarized through a variety of working condition simulations.This paper summarizes the existing calculation experience and the finite element meshing principles,obtaining a finite element analysis method suitable for objects with small parts entering the water at high speed.This research starting from the axial force,lateral force,elastic body translation,rotation trend,cross-section bending moment,etc.,the effects of various water inlet conditions on the above parameters are taken into account.The impact load distribution that is of most interest in engineering,which is influenced by different conditions.In addition,research is made on the angle of attack of projectile,and it is found that both positive and negative angles of attack will have a large adverse effect on water-entry and should be avoided.On the basis of the above work,the complex finite element pre/post-processing software is integrated and secondary-developed.This work is a practical engineering application of the aforementioned simulation analysis work,and a modeling-setting-calculation-post-processing system is built.This functional platform will reduce engineering staff’s working time for familiarizing with software operations and improve efficiency.