Distribution and Evolution Mechanism of Shock Wave Loads from Underwater Simultaneous Explosion of Double Cylindrical Charges

The distribution characteristics and evolution mechanisms of shock wave loads generated by the synchronous underwater explosion of double cylindrical charges are studied to provide a theoretical basis and design foundation for collaborative ammunition strike modes and warhead configuration. The effects of parameters such as charge spacing, azimuth angle, and length-to-diameter ratio on the spatiotemporal evolution and distribution of shock waves are systematically investigated through underwater explosion experiment and numerical simulation. The results indicate that the shock waves generated by the explosion of double cylindrical charges undergo a synchronous superposition on the symmetry plane to significantly enhance the peak pressure, and a secondary pressure peak appears in lateral region due to sequential wave coupling. The influence mechanisms of charge spacing and length-to-diameter ratio on load distribution are further revealed through numerical simulation: the interaction process of double shock waves can be divided into three stages—the convergence of incident waves, the formation of reflected rarefaction waves, and the re-convergence of rarefaction waves. An increase in charge spacing reduces the superimposed pressure on the symmetry plane, but expands the radial distribution ranges of both pressure and impulse. A larger length-to-diameter ratio affects the axial distribution of coupled pressure, leading to a more forward-concentrated pressure profile, while its effect on impulse distribution is relatively minor. Appropriate charge spacing and length-to-diameter ratio can optimally regulate the spatial distribution range of loads to enhance the destructive power against target structures. The findings provide the theoretical support and engineering references for the design of underwater explosion warheads and the damage effect assessment.