Nitrogen Catalytic Recombination on Copper Oxide in Tertiary Gas Mixtures

With a growing demand for cheap access to space and high-speed flight, hypersonic research is experiencing an unceasing interest from worldwide parties. The vehicles designed for this purpose experience flight conditions where real gas effects caused by dissociation and ionization of the air molecules greatly influence the flow conditions and surface heat transfer. This makes the application of conventional perfect gas models ineffective and inaccurate. The study of this high-temperature flight regime and the effects on the flow is called aerothermodynamics. This presentation will introduce the research conducted at the Hypersonics lab of KAIST (South Korea) regarding the catalytic recombination of nitrogen on copper oxide (and copper). Catalytic recombination is a phenomenon where the dissociated air molecules recombine at the surface of the body. The extent to which this recombination occurs does not only depend on the flow condition but is also greatly influenced by the surface material. Copper coated heat flux probes are commonly used as a well-defined reference for experimental catalycity research. However, it has been found that impurities of the probes caused by oxidation (and thus the formation of copper oxide) may have a profound effect on the measured reference heat flux. In order to quantify this effect, heat transfer rates at the stagnation point of a blunt body are measured in a shock tube using thin-film gauges. This thesis presents experimental and theoretical results on the surface catalytic recombination phenomenon occurring in a test gas consisting of a mixture of nitrogen and krypton. The results found in this project will function as a building block towards a better understanding of catalycity which ideally leads to a more accurate design of hypersonic vehicles.AerodynamicsAerodynamics & Wind EnergyAerospace Engineerin