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DOE OSTI · 1679996

Multiphase representation of hotspot formation and growth

Chang, Chong H.·Scannapieco, Anthony J.
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Abstract

Multiphase reacting flow approach has been adopted for modeling of hotspot formation and growth on sub-zonal scale. Mechanical response of the high explosive (HE) is modeled by the Visco-Plastic SCRAM model which includes plastic work, crack growth, and frictional heating along the cracks. In this work a sub-zonal regions with high temperature, hotspots, are modeled as a new phase. Formation and growth of the hotspot phase from the cold phase is modeled as a phase change. Each phase has its own temperature and pressure. Chemical reactions also progress in both phases. The growth of hotspots are determined by the solution of the heat conduction equation with appropriate heat sources due to friction and plastic heating. Sample calculations using the BABBO code show successful detonation calculations with hotspot formation and growth.

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Chang, Chong H., Scannapieco, Anthony J.. 2020-10-09. Multiphase representation of hotspot formation and growth. https://doi.org/10.2172/1679996

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