F4 Steve Son

1. Blast Attenuation by Water Barriers & Small-scale Characterization of Non-ideal explosives; S.F. Son, Purdue • Purpose/Relevance: Conduct fundamental experiments to elucidate physical mechanisms responsible for blast mitigation using water, and design/demonstrate a new small-scale experiment to characterize non-ideal explosives using a microwave interferometer. We are systematically studying the effectiveness, and developing a fundamental understanding, of the interaction of blast waves with water (sprays, sheets, etc.). Laboratory-scale characterization of non-ideal explosives is needed for improved understanding and models. • Innovation: Key technical innovations are using controlled laboratory-based experiments with dynamic time measurements at realistic blast profiles from a unique explosively-driven shock tube to study water mitigation, and the development of an entirely new small scale detonation failure experiment of non-ideal explosives. • This Year outcome: Systematic data sets have been obtained for water barriers, sheets and sprays. Initial modeling has been performed. An unique small scale experiment to characterize non-ideal explosives was designed, built & initial data taken for baseline materials. • Long-range impact: The mechanisms of water blast mitigation are being elucidated. This data & understanding will be useful to modelers/designers interested in using water to mitigate blast. Detailed modeling of the effects of non-ideal explosives used by terrorists is limited by inadequately validated & verified reaction understanding and models. We seek to fill the gap in understanding and data to improve modeling of non-ideal explosives. • Next Year: Modeling of water mitigation systems will be extended and the second phase of experiments will be performed. Small-scale characterization of additional explosives beyond initial base case materials will be performed, as well as parametric studies of particle size and stoichiometry of mixtures. Detonation failure modeling will be performed.

2. Blast Attenuation by Water Barriers & Small-scale Characterization of Non-ideal explosives; S.F. Son, Purdue • Education Students Present & Graduate: Mathew Alley (MS), currently NSWC Crane; Ben Schimizze (current M.S.), Eric Miklaszewski (finishing MS), Robert Janesheski (current M.S.), David Reese (M.S.), and Stephen Strinka (U.G. student) • Papers/Patents/Presentations:“Dynamic Blast Testing,” invited presentation to Force Protection Industries Workshop; “Dynamic Material Characterization of Brain Tissues,” 2nd DoD Brain Injury Modeling Expert Panel Meeting; “Water Blast Mitigation,” abstract submitted to APS Shock Compression meeting and journal paper in preparation; “Detonation Failure Characterization of Non-Ideal Explosives,” abstract submitted to APS Shock Compression meeting. • Transition to Industry or Collaboration with Industry: Participation in “Force Protection Industries Workshop.”