Transport in aluminized RDX under shock compression explored using molecular dynamics simulations

18th APS-SCCM; 24th AIRAPT

Losada, M.^1 ; Chaudhuri, S.^1

ISP/Applied Sciences Laboratory, Washington State University, WA

992101495, United States^1

关键词: Decomposition products;    Diffusing species;    High temperature;    Mean square displacement;    Mechanical response;    Molecular dynamics simulations;    Predictive capabilities;    Shock compressions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/500/16/162002/pdf
DOI  :  10.1088/1742-6596/500/16/162002

来源: IOP

【 摘 要 】

Shock response of energetic materials is controlled by a combination of mechanical response, thermal, transport, and chemical properties. How these properties interplay in condensed-phase energetic materials is of fundamental interest for improving predictive capabilities. Due to unknown nature of chemistry during the evolution and growth of high-temperature regions within the energetic material (so called hot spots), the connection between reactive and unreactive equations of state contain a high degree of empiricism. In particular, chemistry in materials with high degree of heterogeneity such as aluminized HE is of interest. In order to identify shock compression states and transport properties in high-pressure/temperature (HP-HT) conditions, we use molecular dynamics (MD) simulations in conjunction with the multi-scale shock technique (MSST). Mean square displacement calculations enabled us to track the diffusivity of stable gas products. Among decomposition products, H2O and CO2are found to be the dominant diffusing species under compression conditions. Heat transport and diffusion rates in decomposed RDX are compared and the comparison shows that around 2000 K, transport can be a major contribution during propagation of the reaction front.