水射流冲击下纳米铝团簇反应动力学的ReaxFF模拟OA

ReaxFF molecular dynamics simulations were performed to clarify the reactivity and thermal safety risks of metallic alu-minum during the disposal of failed propellants using high-pressure water jets.A nano-aluminum/water impact model was con-structed.Water molecules were assigned impact velocities of 150-400 m·s-1 to represent different water-jet loading intensities.The temperature response,energy evolution,cluster morphology,radial distribution function,coordination number,bond for-mation,and reaction product generation were analyzed.The results show that impact velocity plays a dominant role in triggering the Al-water reaction.As the impact velocity increases,the peak temperature of the system increases from 2563 K significantly.The rapid temperature rise indicates efficient conversion of impact kinetic energy into internal energy and interfacial reaction heat.Structural analysis shows that the Al—Al metallic bonding network undergoes local rupture and rearrangement under im-pact loading.The peak value of the radial distribution function and the average coordination number decrease sharply at approxi-mately 5 ps.This change indicates a rapid transition of the aluminum cluster from an initially dense packing state to a highly dis-persed state.The dispersed structure exposes more reactive aluminum sites and increases the Al-water interfacial contact area.Chemical analysis shows that water adsorption and dissociation are accelerated after structural dispersion.Al—O and Al—H in-termediates form during the early reaction stage,accompanied by the generation of H₂ and H₃O⁺.Large-scale simulations further show that sufficient water supply strengthens the coupling among impact loading,structural dispersion,and chemical heat re-lease.These findings provide atomic-scale dynamic support for optimizing water-jet disposal processes for decommissioned aluminum-containing solid propellants and for predicting on-site thermal safety risks.