The scope of the current work is the experimental characterization of an arc driven plasma wind tunnel and the corresponding high-enthalpy flow. The facility is mainly used for the testing of thermal barrier coatings, the examination of supersonic combustion and the investigation of high temperature thermochemical properties of gases. In addition, the highenthalpy flow can be used for the simulation of physical effects that occur during re-entry to Earth or entry to Mars atmosphere. Therefore, the operational envelope of the facility has been extended in order to achieve a low atmospheric pressure condition and the capability of different test gases, i.e. carbon dioxide, to match different atmospheric conditions. The main focus of the experimental flow examination is the measurement of the rotational temperature of the molecules nitrogen monoxide and carbon monoxide, using laser-induced fluorescence in the ultraviolet range. For the excitation of nitric oxide, a planar laser-induced measurement technique is used and hence, offers a two-dimensional temperature distribution of the flow field. Due to the large energy difference between the ground and excited level of carbon monoxide and the restrictions of the dye laser, a two-photon excitation is applied. The excitation spectra for both molecules are numerically simulated with the aid of a newly developed simulation tool called NOCO-spectra and compared to the measurement results. For calculation of the temperature, the two-line-method, the multi-line-method and the correlation automated rotational fitting method are compared to each other and applied to the spectra obtained in the high-enthalpy flow. For the validation of the simulated spectra and the temperature calculation algorithm, a low pressure flat flame burner with different premixed fuel/air ratios is used. The results succesfully confirm the technical feasibility of the different optical measurement techniques within the plasma wind tunnel and provide a considerably better understanding of the high-enthalpy flow for further ground based tests.
«The scope of the current work is the experimental characterization of an arc driven plasma wind tunnel and the corresponding high-enthalpy flow. The facility is mainly used for the testing of thermal barrier coatings, the examination of supersonic combustion and the investigation of high temperature thermochemical properties of gases. In addition, the highenthalpy flow can be used for the simulation of physical effects that occur during re-entry to Earth or entry to Mars atmosphere. Therefore, t...
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