Supercritical Airfoil Flowfield Measurements

Abstract

Detailed measurements in the transonic flow field about a Whitcomb-type supercritical airfoil profile are presented including surface pressure distributions, far wake surveys, spark schlieren photographs, and a series of vector velocity profiles in the boundary layer and in the near wake. A flowfield composite for the transonic drag rise condition is constructed from these data. The boundary-layer measurements are compared with current correlation and computation schemes, and the importance of viscous thickening effects is demonstrated by the results of wave drag rise calculations for the thickened and unthickened profiles.