Active Control of Disturbation of Wing-Body Rock Induced by Forebody Asymmetric Vortices

The study of free roll oscillation patterns with tip perturbation locations and suppression technique of free-roll-oscillation for wing/body configuration with low swept wing have been carried out at angle of attack alpha = 50 degrees and with Reynolds numbers Re = 1.61x10(5) and 1.93x10(5). The results reveal that there are three types of free roll oscillation patterns: limit cycle wing rock at theta = 0 degrees or 180 degrees; irregular oscillation at theta = 90 degrees or 270 degrees; tiny roll oscillation pattern, if q is on the other positions. A technique of suppressing wing rock motion by rotating nose tip perturbation was developed with higher frequency than one of free roll oscillation and the higher the frequency of rotation of nose tip, the better effect suppression of free wing rock has.