Sandia National Labs FY20 LDRD Annual Report

FY20 ANNUAL REPORT

Rebecca Nylen first interned at Sandia in 2018 as a civil engineering doctoral candidate from Georgia Tech. She’s now a full time staff member on Sandia’s Computational Shock Physics team.

Extreme conditions in the Sandia high-temperature shock tube enable the remote sensing mission. Sandia researchers developed a new capability to shock heat air and other gases to the extreme temperatures and pressures found in conventional explosive events. The method uses a “free-piston” shock tube to generate intense air luminosity, which is then sensed by high-speed emission spectrometers. The LDRD team also developed a novel, highly accurate optical diagnostic to concurrently measure the gas temperature using a pulse-burst laser and Raman spectroscopy. This, in combination with the spectral emission data, enables validation of opacity tables used in NNSA codes to model fireball optical signatures. Collectively, this technology is expected to provide a scientific

underpinning to support multiple national security applications. (PI: Justin Wagner) Illustrative schematic of the free-piston shock tube (top), optical test section (bottom left), and photo of shock-heated air emission obtained during a 7000 K shot (bottom right).

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LABORATORY DIRECTED RESEARCH & DEVELOPMENT