Measurements of the Direct Pitching-Moment Derivatives for Two-Dimensional Flow at Subsonic and Supersonic Speeds and for a Wing of Aspect Ratio 4 at Subsonic Speeds

摘要

Apparatus based on a self-excitation technique has been developed for the measurement of direct pitching-moment derivatives at high speeds, and has proved to function satisfactorily.nMeasurements have been made at subsonic speeds on a two-dimensional RAE 104 aerofoil, both with and without spoilers, and on a rectangular wing of aspect ratio 4 with the same section;and at supersonic speeds (M =1-42 and 1 • 61) on two-dimensional biconvex aerofoils of 74 per cent and 5 per cent thickness.nComparisons with theory are made and discussed.