A new equation of state for aluminized explosives involving the combustion characteristics of aluminum powder after detonation of underwater explosion

The expansion process of detonation products of aluminized explosives is accompanied by the exothermic secondary reaction of aluminum powder. Therefore, the particle size of aluminum powder significantly influences the detonation process, making traditional detonation product equations unsuitable. A new equation of state (EOS) for aluminized explosives that incorporates the secondary reaction of aluminum powder based on its particle size distribution was proposed. The JWL-AlCombustion EOS was embedded into the LS-DYNA software and validated through underwater explosion experiments with hexanitrohexaazaisowurtzitane(CL-20)-based aluminized explosives, showing consistent numerical and experimental results. The study systematically analyzes the impact of different aluminum particle sizes and contents on the energy release behavior of underwater explosions. The results indicate a positive correlation between the peak pressure and shockwave energy and the particle size within a specific range, although the increase is limited. These findings provide crucial theoretical and practical guidance for optimizing the design of aluminized explosives.