Aerodynamic heating measurement on afterbody of hypersonic flight experiment

Measured aerodynamic heating over the ceramic tile region of the Hypersonic Plight Experiment vehicle was obtained on Feb. 12, 1996, Measurements obtained on this lifting hypersonic vehicle during its suborbital flight at velocities up to 3.88 km/s have been compared with heating correlations. Results of the comparisons of obtained measurements to predictions show good agreement for local-to-stagnation Stanton number ratio. Flight measurements also showed that boundary-layer transition occurred on the windward side and that the position of transition moved forward to a location aft of the nose equal to about 30% of the total vehicle length, Local flow conditions, where transition was observed, are evaluated with a criterion for attachment line transition of a yawed cylinder, and the results show fair agreement providing that the surface roughness effect is taken into account. During Right, relaminarization followed transition along the fore part of the vehicle. This relaminarization is surmised to be due to decreasing Reynolds number along the flight path when the effect of variable entropy, caused by nose bluntness, is accounted for.