Study On High Impact Dynamic Transfer Of Multi-body System And Failure Mechanism Of Typical Energy Storage Devices

In modern war,with the update and iteration of defense technology and the underground development of key facilities,the damage efficiency of ordinary ammunition when hitting solid targets is greatly reduced.The multi-body system,taking the hard target penetration projectile as an example,can achieve high-efficiency damage when hitting the solid target.In the multibody system,the penetration fuze accurately detonates the main charge of the warhead after the penetration warhead penetrates the target fortification,so as to achieve accurate attack on the target behind the target.Because of the extreme mechanical impact in the penetration process,the misfire of fuze occurs from time to time.Therefore,modern fuze design methods also put forward higher requirements for the reliability design of fuze.At present,the research on misfire mechanism of penetration fuze mainly includes structural failure and functional failure.In structural failure,the mechanism of fuze overload transmission of multi-body system is unclear.It is generally considered that the fuze overload is the overload of the missile body.However,due to the complexity of the fuze transmission chain and the complex connection between the fuze sensor and the fuze body,the measured overload of the fuze acceleration sensor is greater than that of the missile body.In the functional failure,the failure mechanism of the internal devices of the fuze is unknown,and the failure mechanism of the typical energy storage devices in the process of impact still needs to be further studied.This paper focuses on the dynamic response modeling of multi-body system of penetration projectile and the failure mechanism of typical energy storage devices of fuzes under high impact,which is of great significance to the dynamic response analysis and reliability of penetration fuze.The main work and innovations of this paper are as follows:(1)In order to solve the problem of unknown dynamic transmission mechanism of penetration missile guided multi-body system,the dynamic transmission model of missile guided multi-body system level linkage is established.The complex system of missile body,bottom screw,fuse,buffer medium,circuit board,sensor,etcin the missile-fuze system are divided and evolved into a cascade of several transmission models.The local dynamic transfer model of the projectile-fuze systemprojectile-fuze is established,including the dynamic transfer model between the missile body and the bottom screw,the nonlinear dynamic transfer model of the buffer medium projectile-fuze system,and the fuze acceleration sensor unit transfer model.The unknown parameters of the local transfer model are calibrated by local finite element simulation,which solves the problem of large calculation amount in full coupled finite element simulation of the whole complex system and reduces the simulation time and cost.The nonlinear dynamic transfer model of the penetration projectile-fuze system is established,and the overload signal of the penetration fuze sensor under the action of multi-body system connection is further solved.Finally,it is shown that the calculation results are consistent with the dynamic test results.The error of the simulation results of the projectile-fuze system dynamic transfer model is reduced by 8.3% compared with the fuzzy penetration calculation results,which further verifies the correctness of the nonlinear dynamic transfer model of the projectile-fuze system.The simulation accuracy of missile-fuze dynamic response is improved.(2)Aiming at the influence of buffer media on the attenuation of impact energy of penetration projectile-fuze system,a set of energy analysis method based on the test of buffer materials on the transmission of acceleration signal of projectile-fuze is proposed,and the attenuation law of impact energy flow by different buffer media is revealed.The topological structure of fuze energy flow transmission in the four stages of launch,flight,penetration and after target is established,and the key factors affecting the protection in each stage of the system are analyzed.On the basis of the transmission model of the projectile-fuze system,a set of test methods based on experiments is proposed.The impact energy attenuation law and the influence of the buffer medium on the overload signal transmission are mainly analyzed.The results show that the buffering performance of foam metal materials is better than that of polymer materials,and the peak buffering capacity of foam metal materials is more than 60%;The signal component of foam metal superposition frequency of 11.25 khz is verified,which provides a reference for the design of penetration fuze protection system.(3)Aiming at the failure problem of multi-layer ceramic capacitors in typical energy storage devices under high impact,the failure test of multi-layer ceramic capacitors is focused on,and the failure mechanism model based on mechanical equivalent and impact equivalent circuit is established.The results show that:(1)under high impact,multi-layer ceramic capacitors have parameter drift phenomenon of larger capacitance and larger leakage current.The larger the rated capacitance and withstand voltage of multi-layer ceramic capacitors,the larger capacitance and leakage current drift.The impact of rated capacity is greater,and when the impact overload is within the range of elastic deformation,the capacity and leakage current can still recover to the initial value after impact.(2)The deformation of the opposite area of the electrode is the dominant factor of the capacitance change.(3)The change of impulse overload and leakage current increases exponentially.In addition,the mechanical equivalent model and the equivalent circuit model are established to analyze the mechanism of electrical parameter drift,and the correctness of the model is verified by comparing the numerical simulation with the experimental results,which provides a reference for the failure study of the energy storage capacitor of the penetration fuze.(4)Aiming at the problem that the electrical parameter drift mechanism of lithium battery under high impact is unknown,the research method of the impact sensitive equivalent circuit failure mechanism of lithium battery based on PNGV architecture is proposed.The impact failure test research of lithium battery is focused on,and the parameter drift phenomenon of lithium battery voltage first plummeting and then slowly rising under high impact is clarified.MI-PNGV equivalent circuit model and lithium battery dynamics model(MID-PNGV)are established to reveal the failure phenomenon,mechanism and modeling method of lithium battery under extreme strong impact conditions.The results show that the short-circuit effect caused by the sharp drop of diaphragm resistance is the main factor that causes the rapid drop of voltage at the moment of impact,and the quasi-relaxation effect of lithium ions in the dielectric driven by impact force is the main factor that causes the slow rise of voltage after high impact.It is of great significance to the optimization design of fuse energy(lithium battery)and the improvement of micro system impact resistance under extreme mechanical conditions such as high-speed flying ammunition.(5)Aiming at the dynamic transmission analysis of the penetration projectile-fuze system and the equivalent test verification of typical components,a high impact penetration missile borne test system is designed,which mainly includes the information acquisition principle design of multi-body system,the test circuit design of typical components,the storage control test software design and the acceleration sensor calibration test.A missile borne storage test prototype is developed.A certain type of gun was carried out in the range dynamic test,which verified the correctness of the system transmission model,evaluated the effectiveness of viscoelastic media,foam metal and other cushioning materials for fuse protection,and the failure behavior and protection effectiveness of energy storage devices under high impact,and provided support for penetration missile dynamics transmission solution,typical energy storage device failure and fuse protection methods.