Ground and Flight Experiments to Study Aerothermal Phenomena in Hypersonic Flight Regime

Kurzfassung

Aerothermal heating and thermal protection of spacecraft are main challenges of hypersonic flights. Numerical simulation and design tools still have shortcomings in modelling aerothermodynamic phenomena and structure response at high temperatures. Therefore, reliable experimental data is essential for the design of hypersonic vehicles. Ground testing facilities cannot duplicate the flight environment along the complete flight trajectory, but allow qualification tests at selected conditions in a well characterized environment using advanced intrusive and non-intrusive measurement techniques. Since high enthalpy ground testing facilities are limited in test duration and Reynolds number duplication, low enthalpy wind tunnels are used for aerodynamic stability measurements. Another very important verification and qualification tool is the platform of sound rocket hypersonic flight experiments on scaled vehicles or components. Using multi-stage rocket configurations and flying suppressed trajectory are very promising approaches to gain valuable flight data at hypersonic flight conditions with high integral aerothermal loads leading credible structure temperatures. Extrapolation of results to full scale flight configurations can be done with validated numerical tools. Available data of full-scale interplanetary entry flights is an excellent opportunity to verify it. This lecture contains a dedicated discussion on these topics based on data of past experiments.