Stress And Strain Analysis Of A Gun Launched Solid Rocket Motor Pro Pellant Grain Under High Overload

Gun-launched missile(GLM),which is widely used in the modern battleground,is a class of accurate weapon with the feature of certain point attacking.It is accelerated by a solid propellant rocket engine(SPRE)after it is launched from the gun.During the launching phase,the GLM should support the overload whose value is tens of thousands of gravity acceleration.In the structure of SPRE,solid propellant gain(SPG)is the weakest assembly unit against a high overload.Hence,the research about the stress and strain properties of SPG in the presence of high overload case is reasonable to guarantee the unbroken structure in the launching phase,to promote the reliability of GLM,to realize the desired range and accuracy.Nowadays,both home and aboard researches about mechanical properties of SPG concentrated on the range of high and low variability,lacked the range of middle variability.Based on the dynamic test data of SPG,this paper establishes a series of wide-strain structural equations to describe the mechanical properties at the range low,middle and high variability and simulates the high overload mechanical feedback of SPG in the different cases.The main researches are shown as follows.First,give the comparison of using wide-strain dynamic and static structures in the same working condition,identify the differences between the simulation results,verify the necessity of the application of wide-strain dynamic structure,guarantee the reliability of the follow-up works.In order to research the SPG stress and strain influence resulted from the axial load and the end-face friction in the presence of high overload,the paper simulates and calculates in the two cases,one is for only supporting high axial overload,the other is for supporting both high axial overload and end-face friction.According to the simulation and calculation results,the author hold that the axial load is the biggest issue that affects the inherent biggest von Mises stress and strain,while the stress and strain influence resulted from the friction between the bottom and the paddle of SPG also should be considered.Next,studies the SPG stress and strain influence resulted from the variation of geometry parameters and overload curve.From the study,one can conclude that the biggest total von Mises stress and strain of SPG is seriously affected by aspect ratio of SPG and increase time of the load,but slightly affected by the stress and strain resulted from the friction between the bottom and the paddle of SPG.Finally,in order to research the influence to mechanical properties resulted from the friction the side of SPG and the side wall of the shell,compares the simulation results of non-contacted friction and contacted friction.It is proved that the effect of stress of the inner edge between the side wall and the paddle of SPG is smaller,while of the outer edge is bigger.