全弹状态下固体火箭发动机跌落有限元仿真与试验验证OA北大核心CSTPCD

In order to predict the failure mode,identify the hazards in the case of high-altitude accidental falling of missiles u-sing vertical cold-launch,and understand at the falling safety problem of solid rocket motor,a finite element simulation and experi-mental study on the 30 m falling process of a solid rocket motor under full missile condition was conducted by means of the transient dynamics method.The results show that:during the whole missile falling process,the impact energy is mainly consumed through the plastic deformation and failure of tail cabin,nozzle expansion section,control cabin and ground steel plate,so as to ensure the struc-tural integrity of the combustion chamber case and nozzle convergence section shell.The increase in ground steel plate thickness lead to decrease in the steel plate deformation and the impact time during the impact process,and rise in the maximum stress of the com-bustion chamber case and nozzle.Compared with the 14 mm steel plate,the maximum deformation of the 50 mm steel plate is re-duced by 93%,the impact time is reduced by 34%,and the maximum stress of combustion chamber case is doubled.Oblique falling of the missile with a certain angle contribute to the full play of the bearing capacity of components such as the combustion chamber case and nozzle shell.Reducing the falling angle could lead to decrease in the deformation and failure of the tail chamber and nozzle components during the impact,but rise in the stress of combustion chamber case and nozzle shell,and greater risk of fracture.