A mid-infrared laser absorption diagnostic was deployed to examine the evolution of thermophysical properties across a simulated Mars2020 shock layer in the Electric Arc Shock Tube (EAST) facility at NASA Ames. Rapid laser tuning techniques using bias-tee circuitry enabled quantitative temperature and number density measurements of and CO with microsecond resolution over a shock velocity range of 1.30–3.75 km/s. Two interband cascade lasers were utilized at 4.17 and 4.19 μm to resolve rovibrational lines spanning across to in the asymmetric stretch fundamental bands. In test cases with enough energy to dissociate , a quantum cascade laser scanned multiple transitions of the CO fundamental bands near . The results are compared to the Data Parallel Line Relaxation (DPLR) code and Lagrange shock tube analysis (LASTA) simulations of the shock layer. A numerical simulation of the compressible boundary layer is used to account for measurement sensitivities to this flow feature in the EAST facility. Temperature and species transients are compared to multiple chemical kinetic models. The laser absorption data presented in this work can be used to refine the models used to simulate the aerothermal environment encountered during Mars entry.
Mars2020 Entry Shock Layer Thermochemical Kinetics Examined by Megahertz-Rate Laser Absorption Spectroscopy
Journal of Thermophysics and Heat Transfer ; 38 , 1 ; 129-144
2023-11-06
16 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
NTRS | 2021
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