Aerothermochemistry of High-Temperature Materials for Atmospheric Entry

This work introduces and evaluates an experimental methodology to quantify the atomic recombination activity on the surface of candidate materials for thermal protection systems at high temperatures, when exposed to high-enthalpy non-equilibrium flows.
Investigations are performed in a laboratory environment, where entry flight conditions in Earth’s atmosphere are simulated using the plasma wind tunnel PWK3 of the Institute of Space Systems under the premise of boundary layer similarity. Experiments at PWK3 and boundary layer analyses using the Upwind Relaxation Algorithm for Non-equilibrium flows of the University of Stuttgart, are used for the assessment of recombination coefficients for high-temperature ceramics and superalloys subject to highly dissociated homonuclear diatomic gas flows in thermochemical non-equilibrium.
Finite-rate catalysis models are fitted using the experimentally obtained recombination coefficients, for copper oxide (CuOx), oxide dispersion-strengthened nickel-chromium superalloy (PM1000), and silicon-carbide-coated carbon-carbon-reinforced silicon carbide (C/C-SiC).