Effects on Aerodynamic Performance of Designing Supersonic Wings for Laminar Flow Control.

摘要

A preliminary technique has been developed for the design of wings to be used with supersonic hybrid method laminar flow control systems. This technique has been used to evaluate the effects on aerodynamic performance of designing supersonic wings for laminar flow control. In this design method, a wing is cambered such that it produces and upper-surface streamwise pressure distribution which is favorable for use in a hybrid laminar flow control (HLFC) system, while maintaining a spanwise lifting distribution which will minimize drag-due-to-lift. An existing linear-theory computer program is used to calculate the wing camber definition that produces a desired pressure distribution on the upper surface of the wing with a specified thickness profile. This method was applied to an array of arrow-wings varying in aspect ratio and taper ratio. Each wing planform was then camber-optimized for minimum cruise drag-due-to-lift using current preliminary wing design methods, which optimize the wing's camber of lifting load distribution without regard to the boundary layer type. The total drag of each wing is then estimated by the superposition of zero-lift wave drag, skin friction drag, and drag-due-to-lift. The true effectiveness of laminar flow control wings could then be evaluated by weighing the benefit of the reduced friction drag against the penalty of increased drag-due-to-lift which would be displayed by a wing designed for a laminar flow control system.