Inhibitory effect of hyper-elastic material target on shaped charge jet formation

Abstract

In this thesis, the suppression of jet formation in a shaped charge warhead through the infiltration of hyperelastic materials into the warhead was researched. Three types of rubber materials, which is incompressible and two types of compressible polyurethane materials were selected as hyperelastic materials, and the infiltration effect and jet formation inhibition performance of hyperelastic materials on a shaped charge warhead were investigated through numerical analysis and experiments. In this study, LS-DYNA, a commercial finite element analysis code, was used for numerical analysis. In the numerical analysis, it was predicted that the three types of rubber materials would not have a jet formation inhibition effect due to the insufficient infiltration depth into the warhead, and this was confirmed by the flash X-ray experiment. While, the two polyurethane low hardness materials were found to be highly effective in infiltration into the warhead interior and suppressing jet formation through both the warhead flight collision test and the flash X-ray experiment. Numerical simulations of warhead collision considering the brittle fracture and viscoelastic behavior of the polyurethane low hardness materials were in good agreement with the flight test results. In the jet formation analysis using the 2D Arbitrary Lagrangian Eulerian (ALE) technique, the effect of infiltration depth of the polyurethane low hardness material on jet formation inhibition was investigated and compared with the results of flash X-ray experiments.