Numerical Study On Dispensing Dynamics Of Trans-media Cluster Projectile

Trans-media cluster projectile combines advantages of both trans-media projectiles and cluster projectiles,which have characteristics of quick response,wide-coverage,long underwater-range and awesome efficiency.These features lead this kind of munitions a broad application prospects in trans-media operations.Based on a certain type of trans-media cluster munition,force and motion characteristics of each projectile under different motion and disposition conditions are studied with numerical simulation.These studies are based on a large length to diameter ratio.the effects of different initial conditions on the separation and force&motion characteristics of the projectile during the dispersion are analysed and the regulations are summarised.Firstly,Based on the N-S equation,combining the 6-DOF model and overset mesh,a computational model of the cluster projectile dispersion is established with reasonable boundary conditions and appropriate calculation parameters.The model is verified by calculation.Besides,the force characteristics of a single projectile are analyzed and its stability is calculated.The results show that the projectile has ideal stability under common working conditions.Force and motion characteristics of the projectile in the process of separation were summarized,and the sources of interference were analyzed by comparing the different force and motion characteristics of single projectile and multiple projectiles.At the same time,the interaction boundary of the projectile is calculated with both theoretical calculation and numerical simulation.Based on this,the discussion is taken under the condition of rotating or not and different rotating speed.Rules of projectile motion and force characteristics under different rotating speed is summarized,and the influence of rotating speed on the projectile separating effect is analyzed.The motion and force characteristics of the projectile under different initial spacing conditions are discussed,and the influence of different spacing on the projectile separation effect is obtained.The conclusion is drawn that the main factor affecting the final dispersion of the projectile is the radial velocity at the time of separation.The separation characteristics of the projectile with or without the angle of attack and with different angles of attack are analyzed.It is concluded that the angle of attack should be avoided as the disturbancement.The above work provides a basis for the design of the cluster-type cross-medium projectile and has a certain guiding significance for the follow-up research of this kind of projectile.