A Study On Numerical Simulation Of The Charge Under Typical Packaging Structure Initiated By Fragment Impact

High energy charge is an important part of weapon system which is indispensable, also is an important embodiment for damage power of the whole weapon system. For the charge under typical packing structure, which is on transportation in the wartime, detonated by high speed fragments impact produced by explosion of the various incoming missiles is the main damage mode. This requires that the structure of charge packing not only plays containing and simply protecting the charge effect, but also has a certain ability of anti fragment impact. Because of its special military significance and background, so the related literatures on the fragments shock initiation the package structure charge are rarely public reported at home and abroad.In this paper, for the typical packaging structure of the charge, use the finite element software of ANSYS/LS-DYNA, on the basis of previous studies, using the three ignition and growth model, combining with the dynamic material testing, establishing the numerical model of fragment impact initiation the cover charge with gap, namely fragment impact initiation the "double cover+gap+charge" numerical model. Based on the shock initiation calculation and analysis for fragment parameter and packaging structure of the model, obtaining the shock initiation performance influence laws for fragment parameter and different cover plate materials, thickness, structures and the gap between the cover plate and the charge of the model, thus providing the corresponding analysis method and technology support for the design and damage assessment of the charge anti fragment impact packaging structure.Firstly, carrying out the analysis of equivalent and simplify for the typical charge packing structure, on the basis of, using the dynamic finite element program to carry out the study on three dimensional numerical modeling method of fragment impact initiation cover explosive response analysis. Relative to the numerical model of fragment shock initiation "single-layer homogeneous plate+charge" which studied more currently, the three dimensional numerical simulation model of fragment shock initiation "double cover+gap+charge" is established in this paper according to the real structure of the study object, and on the basis of the initiation process, using the fragment to wear armor and fragment impact initiation bare charge to complete the validation of the model.On the base of the numerical model verification, using the principle of orthogonal test to design the numerical calculation conditions and working conditions. Carrying out the shock detonation calculation for different fragment material, shape, size, the fragment velocity of detonation threshold under different conditions are obtained,using orthogonal test method, obtaining the shock detonation influence law for fragment parameter.Finally, this article carries out the research of packaging structure design of the charge anti fragment impact initiation. On the based of the research of the initiation rules and influence factors in the second part of this paper, through changing the cover material, thickness, structures and the gap between the cover plate and the charge of the model,the anti fragment impact initiation ability of the charge under different packaging structure obtained through calculating. This provides the corresponding analysis method and technical support for the packaging structure design and research of the charge anti fragment impact initiation, which has a great realistic military significance and engineering application value.