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 nearspherical 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 ≈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.

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A suite of instruments including a 100 kHz 4-channel radiometer, a rapid scanning Fourier-transform infrared spectrometer, and two high-speed visible imagers was used to observe the detonation of several novel insensitive munitions being developed by the Air Force Research Laboratory. The spectral signatures exhibited from several different explosive compositions are discernable and may be exploited for event classification. The spectra are initially optically thick, resembling a Planckian distribution. In time, selective emission in the wings of atmospheric absorption bands becomes apparent, and the timescale and degree to which this occurs is correlated with aluminum content in the explosive formulation. By analyzing the high-speed imagery in conjunction with the time-resolved spectral measurements, it may be possible to interpret these results in terms of soot production and oxidation rates. These variables allow for an investigation into the chemical kinetics of explosions and perhaps reveal other phenomenology not yet readily apparent. With an increased phenomenological understanding, a model could be created to explain the kinetic behavior of the temperature and by-product concentration profiles and thus improve the ability of military sensing platforms to identify explosive types and sources.