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arXiv · 1808.08295

A Phonon Boltzmann Study of Microscale Thermal Transport in $\alpha$-RDX Cook-Off

Francis G. VanGessel·Gaurav Kumar·Daniel C. Elton·Peter W. Chung
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Abstract

The microscale thermal transport properties of $\alpha$RDX are believed to be major factors in the initiation process. In this study we present a thorough examination of phonon properties which dominate energy storage and transport in $\alpha$RDX. The phonon lifetimes are determined for all phonon branches, revealing the characteristic time scale of energy transfer amongst phonon modes. The phonon parameters also serve as inputs to a full Brillouin zone three dimensional phonon transport simulation in the presence of a hotspot. In addition to identifying the phonon mode contributions to thermal transport, and as N-N bond breaking is integral to disassociation, we identify phonon modes corresponding to large N-N bond stretch analyzing the manner in which these modes store and transfer energy.

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Francis G. VanGessel, Gaurav Kumar, Daniel C. Elton, Peter W. Chung. 2018-08-24. A Phonon Boltzmann Study of Microscale Thermal Transport in $\alpha$-RDX Cook-Off. https://arxiv.org/abs/1808.08295

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