WING-FLUTTER MITIGATION BY TARGETED ENERGY TRANSFERS INDUCED BY AN ESSENTIALLY NONLINEAR ATTACHMENT

The problem to be addressed here is the mitigation of limit cycle oscillations (LCO) in a rigid in-°ow wing with nonlinear heave and pitch sti®nesses in quasi-steady °ow, using targeted energy transfer (TET). We show through simulation and Wavelet transforms that LCO formation is a process of resonance capture, with heave response triggering the pitch LCO. With the addition of a lightweight, fully passive attachment { a nonlinear energy sink (NES) { to the wing, we analytically predict three distinct mechanisms for LCO mitigation: repeated suppressed burst-outs, partial and complete suppressions of aeroelastic instability. Subsequent wind-tunnel experiments conducted in the Nonlinear Aeroelastic Test Apparatus (NATA) at Texas A&M University fully support these results.