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arXiv · 1502.00673

Mesoscale simulations of shockwave energy dissipation via chemical reactions

Abstract

We use a particle-based mesoscale model that incorporates chemical reactions at a coarse-grained level to study the response of materials that undergo volume-reducing chemical reactions under shockwave-loading conditions. We find that such chemical reactions can attenuate the shockwave and characterize how the parameters of the chemical model affect this behavior. The simulations show that the magnitude of the volume collapse and velocity at which the chemistry propagates are critical to weaken the shock, whereas the energetics in the reactions play only a minor role. Shock loading results in transient states where the material is away from local equilibrium and, interestingly, chemical reactions can nucleate under such non-equilibrium states. Thus, the timescales for equilibration between the various degrees of freedom in the material affect the shock-induced chemistry and its ability to attenuate the propagating shock.

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Edwin Antillon, Alejandro Strachan. 2015-02-02. Mesoscale simulations of shockwave energy dissipation via chemical reactions. https://doi.org/10.1063/1.4908309

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