Metal Particle Heating and Acceleration in Condensed Explosives

For condensed explosives containing metal particle additives, a characteristic parameter relating the detonation reaction zone length (L$_{r}$) to the particle size (d$_p$) can be defined as $\delta $ = d$_{p}$/L$_{r}$. The detonation reaction zone length is typically 0.01 $<$ L$_{r}<$ 100 mm, whereas metal particle sizes of 100 nm $<$ d$_{p}<$ 1 mm can be employed. This indicates a potential range of 10$^{-6} <\delta <$ 10$^{2} $. The limiting case of $\delta \ll$ 1 involves frozen shock/particle interaction; for $\delta \gg$ 1 the interaction consists of a thin-detonation-front diffraction followed by expanding products flow. The intermediate case of $\delta \approx$ 1 has been studied previously as a function of metal mass fraction and particle packing to determine momentum and heat transfer during the detonation interaction time. Results indicate a strong dependence of particle acceleration and heating rate on $\delta $ for high metal mass fraction conditions. The present study employs 3D mesoscale simulation to further conduct parametric studies in the 0.1 $\le \delta \le$ 10 range by varying the particle diameter, particle metal and explosive material. The results are quantified to determine macroscopic physical models for particle acceleration and heating.