Mesoscale modeling of hypervelocity impacts using the CTH shock physics code

Journal Article · 26 November 2019 · International Journal of Impact Engineering

DOI: https://doi.org/10.1016/j.ijimpeng.2019.103462 · OSTI ID:1595424

Bouchey, Stephanie N. Q. ^[1]; Hollenshead, Jeromy T. ^[1]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Material fragmentation after a hypervelocity impact is vital to predictive electro-optical and infrared (EO/IR) modeling. Successful comparisons with data require that hot, submicron fragments are generated in such impacts; yet, experimental data has so far been unable to produce fragments of this scale. The purpose of this work was to investigate how modeling assumptions of macro-scale, bulk materials might influence the generation of debris in hypervelocity impacts and ultimately the predicted EO/IR signatures of these debris clouds. Sphere-on-plate impact simulations simplified the comparison of different modeling approaches. In one set of simulations, materials were modeled with the traditional, bulk approach. Those findings were compared to simulations run with the mesoscale material grain structure explicitly modeled. This study focused on the comparison of two parameters that are tied directly to the EO/IR signature: strain rate at failure (a proxy for debris fragment size) and material temperature. Interfaces between grains, here due to void insertion, resulted in the most notable change in both the strain rate at failure and material temperature. Shock reflections from grain-void interfaces induced higher strain rates and material temperatures, and it is expected that similar effects may be produced from inclusions or dislocations in real materials. Thus, interfaces within a material may play an important role in producing smaller hot debris frag

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC04-94AL85000; NA0003525
• OSTI ID: 1595424
• Report Number(s): SAND-2020-0069J; 681931; TRN: US2100876
• Journal Information: International Journal of Impact Engineering, Vol. 137, Issue C; ISSN 0734-743X
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English