Influence of Initiation Diameter on Formation of Collinear EFP with Fins from Warhead with Double Layer Liners

Abstract To improve the aerodynamic performance of collinear EFP from warhead with double layer liners, the forming process of collinear EFP with fins and the effect of the initiation diameter on the formation of collinear EFP with fins under four-point initiation was analyzed by using LS-DYNA software. The results showed that it could form symmetrical and uniform fins at the tail of collinear EFP by using multi-point initiation, which effectively improved the aerodynamic performance of collinear EFP. The impact of initiation diameter on forming parameters of collinear EFP with fins was mainly reflected in the shape parameters but had little influence on the velocity. The initiation diameter was bigger, the length-diameter ratio γ and wingspan-diameter ratio β of the front EFP increased linearly while the wingspan and wingspan-diameter ratio β of the rear EFP decreases, and the reduction rate decreased gradually.