RADAR ENERGY ABSORBING DEFORMABLE LOW DRAG VORTEX GENERATOR

摘要

A family of Radar energy Absorbing Deformable Low Drag Vortex Generators (RAD-LDVG) is described herein. This family of devices are fabricated in such a way that it can conform to aircraft surface features while reducing radar returns from structural details. Vortex generators (VGs) are typically used to reattach or smooth gross flowfields over aircraft surfaces. By doing so, an airfoil or wing can maintain attached flow at higher angles of attack and/or higher lift coefficients than one without the VGs. These devices are also used to reattach and/or smooth flows that encounter crossflow-induced instabilities and/or adverse pressure gradients on the upper surfaces of wings or near aircraft boattails. Other uses include reduction of buffet, vibration, flutter, cavity resonance or general bluff-body pressure drag reduction. Although conventional rigid VGs do generate vortical aerodynamic structures, two major problems are often experienced: i.) the inability to conform to curved surfaces, ii.) the generation of radar cross-section spikes produced by the VGs themselves.

主权项

1. A device which is shaped so as to produce streamwise vortices when attached to an internal or external surface of an aircraft and exposed to airflow, comprising:
a vortex generator having an upstream end and a distal downstream end with respect to a flowfield, where the vortex generator has a lateral width and a vertical height and a bottom surface mountable to a surface of an aircraft skin where the vertical height of the vortex generator is tapered to increase from the upstream end to the distal downstream end forming a concave upper surface and where the lateral width of the vortex generator is tapered to decrease from the upstream end to the distal downstream end forming concave sidewalls; said bottom surface mounted flush to the surface of the aircraft skin; and said vortex generator constructed of a material sufficiently flexible to mount flush on a nonuniform aircraft skin and to deform responsive to increased pressure from the flowfield to thereby reduce said vortex generators vertical height from an initial height to a reduced height.