Passive Control of Thin-Wing Flutter
Date of Award
Master of Science in Engineering
Dr. Tianshu Liu
Dr. Javier Montefort
Dr. Parviz Merati
Masters Thesis-Abstract Only
Restricted to Campus until
The present work describes a method for thin-wing flutter control using an array of small, flexible, rectangular polymer fins attached near the leading edge on the upper surface of a wing to manipulate unsteady flow structures. The dynamic deformation of a rectangular flat-plate wing along with the motions of the fins relative to the wing’s surface are measured using a high-speed videogrammetric system in a low-speed wind tunnel. The major vibration modes of the baseline wing and the wing with fins are extracted. It is found that flutter, particularly near the dominant first torsion mode, is considerably suppressed in the ranges of the freestream velocities and angles of attack investigated. To observe the changes of the flow field induced by flexible fins, the velocity fields over the rectangular flat-plate wing were measured using PIV. The standard deviation of velocity, which characterizes the variation of the unsteady flow, is significantly suppressed for the wing with fins, which results in flutter suppression. Lastly, the effect of the fins is examined as it applies to the lift and drag forces experienced by the wing. Addition of the fin to the wing does not significantly affect the mean lift or drag forces. However, there is a noticeable decrease in the standard deviation of the lift and drag forces for the wing with fins, which provides further evidence of the flutter suppression caused by the fins.
Pohl, Nicholas L., "Passive Control of Thin-Wing Flutter" (2012). Master's Theses. 73.