Embedded particle size distribution and its effect on detonation in composite explosives

Abstract

This paper discusses the effects of stochastically varying inert particle parameters on the long-term behaviour of detonation front propagation. The simulation model involves a series of cylindrical high explosive unit cells, each embedded with an inert spherical particle. Detonation shock dynamics theory postulates that the velocity of the shock front in the explosive fluid is related to its curvature. In our previous work, we derived a series of partial differential equations that govern the propagation of the shock front passing over the inert particles and developed a computationally efficient simulation environment to study the model over extremely long timescales. We expand upon that project by randomising several properties of the inert particles to represent experimental designs better. First, we randomise the particle diameters according to the Weibull distribution. Then we discuss stochastic particle spacing methods and their effects on the predictability of the shock wave speed. Finally, we discuss mixtures of plastic and metal particles and material inconsistency among the particles.

Keywords:

• metal-loaded high explosives
• detonation shock dynamics
• wave propagation
• stochastic behaviour
• numerical simulation

Acknowledgements

We would like to thank Allison Gardner for her consultation on the statistical analysis, our coworkers for their advice and moral support, and the University of Illinois in Urbana-Champaign for the use of their facilities.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Eglin Air Force Base [grant number FA8651-10-1-0004; Advanced Modeling and Simulation Technologies for Micro-Munitions]; the Air Force Office of Scientific Research [grant number FA9550-06-1-0044; Analysis of Multi-Scale Phenomena and Transients in Explosive and Complex Energetic Systems], [grant number FA9550-12-1-0422; Computational and Analytical Modeling of Advanced Energetic Materials].