Shaped Charge Jets Interaction with Passive and Reactive Armor : A Complete Multi-Scale Approach

Abstract On the battlefield, armored vehicles can be attacked by shaped charge warheads from small and medium caliber (bomblets, RPGs, loitering munitions) to large caliber (tandem missiles, HEAT rounds). Different technologies of protection (inert and energetic) are successfully used to defeat these threats but they are mainly designed by experiments. A global multi-scale approach is proposed to model the interaction of shaped charge jets with protection systems focused on the precise assessment of the precursor which is mainly responsible for the final penetration in passive armor. The formation, elongation and fragmentation of shaped charge jets are well represented thanks to the -SPH-ALE scheme implemented in the Impetus Afea Solver, the identification of material constitutive models as well as optimization of particle discretization. Furthermore, the modeling of the different stages of jet penetration is in good agreement with experiments in semi-infinite Rolled Homogeneous Armor targets for medium up to large caliber threats. Behind explosive reactive armor, the correct assessment of the precursor allows to assess the final crater depth by focusing on the explosive initiation at the earliest instants. Different approaches are presented regarding time and location of the detonation of a low sensitive explosive and its behavior considering its critical diameter.