Investigation On Deployment Mechanism And Damage Effects Of Structure Under Explosion Loading

With the rapid development of morden military equipment technology,and the air-to-air and surface-to-air missile weapon system is constantly updated.The development of the warhead is required to flexible,light weight and high power,and which requires of the warhead not only to limit the size and weight,but also to achieve high efficiency damage of the target.The variable geometry warhead is a kind of structure with high efficiency damage ability,which is the best choice for satisfy the above requirements.The research on this warhead technology will greatly reduced the gap between our country and the developed countries in the warhead department.It has very important application value in the field of national defense industry.In this thesis,the dynamic response mechanism under explosive loading and damage power and other related question of the variable geometry warhead are systematically studied by theoretical analysis,numerical simulation and experimental test method,and the main works are as follows:(1)The calculation model of fuze delay time is established for directional warhead based on missile target-encounter coordinate system.Compare with relative efficiency of several typical warhead structures,and the variable geometry warhead has absolute superiority.The influence of fuze delay time is analyzed through paramenters of calculation model.The analysis results show that the fuze detection range,fuze tetection angle,relative velocity vector and missile approaching status have a great influence.The opimum fuze delay time under the condition of general missile-target encounter is given,i.e.the fuze delay time of the head-on status is 2.521ms~10.576ms,and which of the chase status is4.487ms~13.769ms.Accordingly,the opening time of main charge part of the variable geometry warhead is presented.(2)Investigate the dynamic response mechanism of the variable geometry warhead under explosives loading.Based on the typical structure of the variable geometry warhead,the dynamic response equation of the main charge part is eastablished.Solving centroid trajectory with the initial condition of explosives loading,and get the complete dynamic process of the main charge part.The simulation result is coincided with the theoretical,and the reliability of theroretical analysis and numerical simulation is verifiled by explosion driving experiments.Compareing the experimental results to optimize the experimental structure,and make the opening time of main charge part to reach 9.5ms.(3)The optimization method of the the variable geometry warhead structure is proposed.The energy absorption scheme is given for the failure reason of the limit hinge,and which was verified by numerical simulation and experimental tests.The simulation results show that the optimized limit hinge can reduce the impact load,and which make the overall energy absorption rate of hinge to 45%.The results of the experiment verified the feasibility of the optimized scheme and the reliability of the simulation results.Moreover,shorten the opening to 7.6ms.(4)Based on the damage mechanism of the variable geometry warhead,the design schemeof the fragment layer is proposed and the damage power evaluation is carried out.The effect of fragment performance with different groove paraments is compared by numerical simulation,and the best design scheme is given.The damage power experiment of various working conditions is carried out,and obtained the the damge power of the variable geometry warhead by analyzing the experimental data.The experimental results show that the average velocity of impacting target of fragments is 1140.3m/s,and the actual penetration probability is more than 90%.In addition,the fragment density reached more than 150 pieces/m~2 in the square damage region which dimension is 1.2m×1.2m.The velocity and distribution of framgnts obtained by simulation are well coincident with the experimental results,and the reliability of numerical simulation method is verified,which is provide for the lethality design of the variable geometry warhead.