The Study Of Pyroshock Coupling Effect Based On Clamp Band Separation System

The spacecraft will experience complex vibration,noise and impact environments during its operation.The impact environment mainly comes from the separation process.The spacecraft structure and sensitive components may fail under this impact,which may leading to the failure of space missions.Because of its high reliability,the clamp-band separation system is widely used for separation of spacecraft or satellites from the launch vehicles.The impact of separation of the clamp-band separation system mainly comes from two aspects.On one hand,the explosion bolt will have a great impact on the adjacent structure when it is exploded,which will propagate in the structure in the form of high-frequency,high-level material stress waves.producing high-impact,broadband instantaneous mechanical response in the structure;on the other hand,under the influence of the band with preload,the interface ring storages strain energy due to the deformation,when the system is unlocking,the interface ring loses its bandage.The strain energy converts into kinetic energy gradually,causing vibration shock thereby.In this paper,the LS-DYNA dynamics method is used to simulate the local and global theoretical model of the clamp-band separation system.The characteristics of each impact and the studied the coupling effect between them deeply.In chapter 1,the background and significance of the subject are introduced,reviewing a series of domestic and overseas advance briefly.Emphasize the importance of the impact environment.Analyzed the gaps in the coupled parts of the impact source in recent years,and then determined the content of this paper.Chapter 2 uses the ALE method to simulate the fracture process of explosive bolts,describes the explosion process in detail.Analyze the equivalent plastic strain of the unit at the notch and compare the impact response of the push rod and the shell.The rationality of the package-band separation structure model was verified.And the characteristics of the explosive impact were analyzed.In Chapter 3,the method of force loading is used instead of bolt preloading to simulate the strain energy release impact in the separation process of the V-band separation system.A simplification-tape separation model was established to study the energy distribution in the equilibrium state of the band and obtained the strain energy release impact characteristics.Meanwhile,this paper make some analysis of the factors that may affect the impact of strain energy release,including the number of V-segments and the preload of the band,providing a theoretical basis for reducing the impact of separation.Chapter 4 simulated three different conditions: Explosive-only model,strain-energy-only model,and the coupling model.The near-field measurement points at the connection between the bolt and the band and the response results of the measurement points at the middle and far field at the upper end of the frame separation were compared and analyzed,and the coupling laws of the two impact sources were given qualitatively.