Free-flight measurements of pressure distribution at transonic and supersonic speeds on bodies of revolution having parabolic afterbodies

Abstract

Free-flight measurements have been made of the pressure distributions over a series of related afterbodies attached to a common cone-cylinder body of revohition. The Mach number range covered was from 0.9 to 1.5 and the Reynolds number range from 31 to 65 x 10power6. The experimental results were in reasonable agreement with theoretical values calculated by the method of characteristics and confirm the usefulness of the supersonic similarity law as a means of predicting drag. Measurements of base pressure were qualitatively in agreement with estimates but quantitatively the agreement was not good. Limitations in the experimental technique and in certain cases the occurrence of flow separation are jointly held responsible for the discrepancies. The measured boundary-layer displacement thicknesses on the afterbody were in good agreement with estimated values.