Accession Number : ADP004154

Title :   Wing Rock Flow Phenomena,

Corporate Author : LOCKHEED MISSILES AND SPACE CO INC SUNNYVALE CA

Personal Author(s) : Ericsson,L. E.

Report Date : 1984

Pagination or Media Count : 11

Abstract : Flow mechanisms that can generate wing-rock type oscillations are described. It is shown that the slender wing rock phenomenon, the limit cycle oscillation in roll observed for very slender delta wings, is caused by asymmetric leading edge vortices and that vortex breakdown can never be the cause of it as it has a damping effect. For that reason slender wing rock is only realized for delta wings with more than 74 deg leading edge sweep for which asymmetric vortex shedding occurs before vortex breakdown. For straight or moderately swept wings the flow mechanics causing wing rock is two-dimensional in nature, closely related to the dynamic stall phenomenon. Pointed forebodies provide a third flow mechanism, asymmetric vortex shedding sensitive to body motion, which can generate a rocking motion of a slender vehicle unless it is completely axisymmetric. (Author)

Descriptors :   *Vortex shedding, *Delta wings, Unsteady flow, Oscillation, Leading edges, Asymmetry, Wings, Slender bodies, Vortices, Damping, Two dimensional flow, Flow fields, Coupling(Interaction), Fluid mechanics, Stalling, Wing body configurations

Distribution Statement : APPROVED FOR PUBLIC RELEASE