Influence of lining thickness and impedance on the explosion driving of prefabricated fragments

Prefabricated fragments may deform or crack during explosion driving process, which is adverse to kinetic energy damage. Setting up lining between explosive charges and prefabricated fragments is considered to be an effective way to prevent the excessive load on fragments. This paper studied the influence of lining thickness and impedance on explosion driving of prefabricated fragments based on LSDYNA finite element simulation. Steel lining of different thickness between 0~14mm have been studied, as well as steel liner with Kevlar fiber. Fragments accelerated drive process were analysed from the perspective of energy conversion. The results show that the initial speed of the fragment is mainly affected by the quality of the lining and the fracture radius. The axial deformation of the fragment is positively correlated with the initial impact pressure. Steel-fiber composite lining can reduce the shock wave pressure transmitted though, which significantly reducing the initial pressure on the fragments.Low-impedance Kevlar fiber on the outside of the 4340 steel lining can reduce the initial impact pressure of the fragment by about 75%.