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arXiv · 1606.02134

Microscopic origin of self-similarity in granular blast waves

Matthieu Barbier·Dario Villamaina·Emmanuel Trizac
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Abstract

The self-similar expansion of a blast wave, well-studied in air, has peculiar counterparts in dense and dissipative media such as granular gases. Recent results have shown that, while the traditional Taylor-von Neumann-Sedov (TvNS) derivation is not applicable to such granular blasts, they can nevertheless be well understood via a combination of microscopic and hydrodynamic insights. In this article, we provide a detailed analysis of these methods associating Molecular Dynamics simulations and continuum equations, which successfully predict hydrodynamic profiles, scaling properties and the instability of the self-similar solution. We also present new results for the energy conserving case, including the particle-level analysis of the classic TvNS solution and its breakdown at higher densities.

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Matthieu Barbier, Dario Villamaina, Emmanuel Trizac. 2016-06-07. Microscopic origin of self-similarity in granular blast waves. https://doi.org/10.1063/1.4961047

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