The Jet Flow Field Of Submunition Dispersal Process And Its Influence On The Projectile Motion

In this dissertation, the gasbag rupture jet flow structure in submunition dispersal process and its influence on the projectile motion are deeply researched by theoretical analysis and numerical simulation. Analysis of the main includes following work:(1) Three-dimensional dynamic model of the combustion gasbag rupture projector structure was established, the gasbag rupture jet flow field was simulated by using Computational Fluid Dynamics combined with the six degree of freedom equation of rigid body motion and dynamic mesh technique.(2) The jet flow stucture characteristics of free jet and the gasbag rupture jet which were generated in the submunition dispersal process were compared, the variation of the internal pressure of gasbag was obtained. The results showed that, the existence of the projectile had a great effect on the jet space, and the gasbag rupture jet flow structure was very different from the free jet flow structure;(3) The gasbag rupture jet with different ruptured position at gasbag were simulated, the variation of the internal pressure of gasbag and its influence on projectile motion were obtained.. The conclusion illustrated that when the gasbag ruptured at the center position, there had greatest impact on the internal pressure of gasbag. When the gasbag ruptured at the center or at the short side position, there had greatest impact on the attitude of projectile.(4) The gasbag rupture jet with different initial pressure of gasbag on the basis of the research of the gasbag ruptured at the short side position were simulated, and its influence on projectile motion was analyzed. The results suggested that the higher of the initial pressure of gasbag was, the greater impact on the projectile motion attitude, and also, the higher of the initial pressure of gasbag was, the average pressure of gasbag, the average pressure of the gasbag laceration and the maximum pressure of projectile declined more slowly.The results of this study has great significance for estimating the projectile flight trajectory, understanding the mechanism of balloon rupture and the influence law on projectile motion of gasbag rupture jet flow, improving the reliability and safety of submunition separation.