An experimental investigation of the structure of a leading-edge vortex

Abstract

An experimental investigation of one of the pair of vortices, produced above a delta wing at an incidence of 14.9 deg, has been made by means of a five-tube yawmeter head. Traverses through the axis of the vortex, at three stations along the wing, suggest that it may conveniently be regarded as divided into three regions. These comprise an outer and an inner region, in both of which scale effects are evident, and a region between these wherein the flow is effectively conical. Within the inner region, which is approximately 5 per cent local semi-span in diameter, the gradients of total head, static pressure and velocity are very high. Here also, circumferential velocities equal to free-stream velocity and axial velocities of over 2.3 times this were recorded.