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DOE OSTI · 1887148

Developing Reaction Chemistry Models from Reactive Molecular Dynamics: TATB

Kober, Edward M.
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Abstract

Reactive Molecular Dynamic (RMD) are used to simulate the cook-off chemistry of TATB at a variety of fixed density and fixed temperature conditions. The chemical transformations are monitored using a Coordination Geometry Analysis (CGA) approach which tracks which atom types are bonded to each specific atom. This particularly identifies oxidation state changes that occur during the transformations. Correlations between these different chemical changes are identified using a Non-negative Matrix Factorization (NMF) approach. These identify reduced order chemistry models for the TATB system which contains six components whose concentration profiles are a function of both the temperature and density/pressure. The time histories of these transformations appear to show exponential growth/decay properties that could be fit with Arrhenius rates. These components should form the basis of deflagration rate models for these materials which could then be used in mesoscale simulations to analyze accidental initiation, shock-to-detonation and detonation propagation.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYTATBreactive molecular dynamicsreduced chemistry models

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Kober, Edward M.. 2022-06-15. Developing Reaction Chemistry Models from Reactive Molecular Dynamics: TATB. https://doi.org/10.1002/prep.202100386

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