The Use of Conical Camber to Produce FlownAttachment at the Leading Edge of a Delta Wing and to Minimize Lift-Dependent Drag at Sonic and Supersonic Speeds

摘要

In an attempt to avoid flow separation at the leading edge of a thin delta wing with subsonic leading edges, an attachment line is prescribed there. This is done by requiring the load, as predicted by attached-flow theory, to vanish along the leading edge at the design lift coefficient. For sonic speed, a complete account of this flow is given in terms of slender-wing theory and the load distributions corresponding to arbitrary conical camber are calculated. The lift-dependent drag for a given lift is then minimized with respect to the coefficients of a linear combination of these load distributions. It is found that the lift-dependent drag factor for these conically-cambered wings approaches the value it takes for the attached flow (in which leading-edge suction occurs) past the uncambered wing at the same Mach number, as more terms are included in the linear combination.