The problem of predicting aerothermodynamic heating for hypersonic vehicles is examined, and the surface reactions (catalytic) contribution is modeled using current assumptions. Surface thermal load depends, in general, on the entire flowfield, but direct dependence is on surface temperature, driving radiative cooling and surface recombination rates, and on diffusional velocities at the interface. A critical area in modeling thermal load is availability of accurate transport properties; gas kinetics is also important, but not as much als previously thought, at least for LEO re-entry problems. Current data for surface rates are analyzed, and more detailed information on physics is presented that is in part used to build a zeroth-order new model for catalytic recombination over TPS materials. The simple model can save on experimental time and effort; better models, including selectivity due to vibrational energy exchange between gas and surface, may still be built starting from that presented, and will require more information concerning the binding process between O, N atoms and metals.
Modelling catalytic recombination heating at hypersonic speeds
Modell der Erwaermung durch katalytische Rekombination bei Ueberschallgeschwindigkeit
AIAA-Papers ; Jan ; 1-16
1989
16 Seiten, 9 Bilder, 59 Quellen
Conference paper
English