Numerical Simulation of the Structure of Composite Liner to Enhance After-Effect

To address the problem of the after-effect of the enhanced shaped charge jet penetrating armor, the cone-shaped flat-topped conical copper-aluminum double-layer composite charge structure was designed. Numerical simulation of the jet forming and penetration process of the steel-aluminum interval target with this structure was performed using Euler dynamics software SPEED. And the influence rules of parameters such as the height ratio $\varepsilon$ of the inner and outer liner, the cone angle α of the liner on the compound jet forming and the penetration of the interval target plate were analyzed. The research results show that the head velocity of the compound jet declined first and then rose with the increase of $\varepsilon$. When $\varepsilon$=1/2, a coaxial copper and aluminum compound jet element with similar velocity can be formed, which is conductive to strengthening the after-effect after the interaction between the aluminum jet and the target. When $\varepsilon$ is 55°～60°, the middle section of the compound jet is a concentrated aluminum jet element, which is more conducive to the intensified explosive reaction after penetration. It is found that the simulation results of the optimized parameters of the compound liner structure are perfectly consistent with the experimental results published in the literature. This research results have a certain reference value for the enhanced after-effect shaped charge design.