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DOE OSTI · 1574453

Thermal conductivity of energetic materials

Abstract

Here, thermal conductivity has been confirmed for a variety of energetic materials (EMs) using finite element analysis (FEA) and cookoff data from the Sandia Instrumented Thermal Ignition (SITI) experiment. Materials studied include melt-cast, pressed, and low-density explosives. The low-density explosives were either prills or powders with some experiments run at pour density (not pressed). We have viewed several of our thermal conductivities with those in the literature as well as investigated contact resistance between the confining aluminum and explosive, multidimensional heat transfer effects, and uncertainty in the thermocouple bead positions. We have determined that contact resistance is minimal in the SITI experiment, the heat transfer along the midplane is one-dimensional, and that uncertainty in the thermocouple location is greatest near the heated boundary. Our values of thermal conductivity can be used with kinetic mechanisms to accurately predict thermal profiles and energy dissipation during the cookoff of explosives.

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Lawless, Zachary D., Hobbs, Michael L., Kaneshige, Michael J.. 2019-10-23. Thermal conductivity of energetic materials. https://doi.org/10.1080/07370652.2019.1679285

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36 MATERIALS SCIENCE↗