This paper presents critical effects of on-blade active control surface motion on the aeroelastic response of a rotor blade in forward flight. Aeroelastic simulations conducted with an in-house high fidelity solver indicate that blades-wake interactions caused by control surface deflections change the frequency content of the rotating frame blade loads. Specifically at the 11 rev frequency for a four-bladed rotor system this effect is predominant. The previously recorded information on variations in aerodynamic loading obtained from lifting line theory and comprehensive grid and/or vortex based solvers are shown to be due to blade-wake modeling differences. To prevent possible closed-loop instabilities at the control critical frequencies, either in controller synthesis these modeling differences must be accounted for or the reduced-order models used in controller synthesis must be identified from high-fidelity simulations to accurately capture these blade-wake interactions. Copyright

68th American Helicopter Society International Annual Forum 2012
Department of Mechanical and Aerospace Engineering

Ulker, F.D. (Fatma Demet), Voutsinas, S. (Spyridon), Riziotis, V. (Vasilis), & Nitzsche, F. (2012). On the necessity of high-fidelity aeroelastic modeling of on-blade control surface for helicopter vibration suppression. In Annual Forum Proceedings - AHS International (pp. 1270–1279).