A theoretical and experimental investigation of the flow over a family of rectangular wings of biconvex section at M = 1.42

Abstract

An account is given of experiments made at M = 1.42 using three rectangular half-wing models having biconvex sections with thickness ratios 0.04, 0.06 and 0.08, mounted on a reflection plate. Measurements were made of the pressure on the upper surface of the wing and of pressure and flow direction in the neighbourhood of the wing. tip. Direct shadow photography and observation of surface oil patterns enabled various details of the flow to be visualised. The results are correlated with the linearised theory and with certain second-order modifications to this theory. It is found that in general the linearised theory provides a sufficient approximation to the detailed flow only for the thinnest wing at very small incidences. In most cases the suggested modifications effect a considerable improvement.