Fireball and shock wave dynamics in the detonation of aluminized novel munitions

High-speed 4-kHz visible imagery from 13 field detonations of aluminized RDX munitions with varying liner compositions are collected to study shock wave and fireball dynamics. The Sedov–Taylor point blast model is fitted to shock front temporal history data, and blast wave characteristics are interpreted by varying the energy release factor s and blast dimensionality $n$. Assuming a constant rate of energy release ($s$ = 1), the Sedov–Taylor model establishes a near-spherical expansion with the dimension $n$ = 2.2–3.1 and shock energies of 0.5–8.9 MJ. These shock energies correspond to efficiencies of 2–15% of the RDX heats of detonation. A drag model for the fireball size yields a maximum radius of $\approx$ 5 m, which is consistent with the luminous fireball size in visible imagery, and initial shock speeds corresponding to Mach numbers of 4.7–8.2. Initial shock speeds are smaller than the RDX theoretical maximum speed by a factor of 3–4. Shock energy decreases if aluminum is in the liner rather than in the high explosive.