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DOE OSTI · 1432627

Constrained optimization framework for interface-aware sub-scale dynamics models for voids closure in Lagrangian hydrodynamics

Barlow, Andrew·Klima, Matej·Shashkov, Mikhail
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Abstract

In hydrocodes, voids are used to represent vacuum and model free boundaries between vacuum and real materials. We give a systematic description of a new treatment of void closure in the framework of the multimaterial arbitrary Lagrangian–Eulerian (ALE) methods. This includes a new formulation of the interface-aware sub-scale-dynamics (IA-SSD) closure model for multimaterial cells with voids, which is used in the Lagrangian stage of our indirect ALE scheme. The results of the comprehensive testing of the new model are presented for one- and two-dimensional multimaterial calculations in the presence of voids. Finally, we also present a sneak peek of a realistic shaped charge calculation in the presence of voids and solids.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS97 MATHEMATICS AND COMPUTINGInterface-aware sub-scale closure modelsLagrangian hydrodynamicsMultimaterial cellsVoid closure

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Barlow, Andrew, Klima, Matej, Shashkov, Mikhail. 2018-04-02. Constrained optimization framework for interface-aware sub-scale dynamics models for voids closure in Lagrangian hydrodynamics. https://doi.org/10.1016/j.jcp.2018.03.034

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