Suppression of aeroelastic instability with a nonlinear energy sink: Experimental results

The presence of limit cycle oscillations within the flight envelopes of existing aircraft is well documented. Future air vehicle designs are als o likely to encounter limit cycle oscillations under certain loading conditions. Thes e steady-state constant amplitude oscillations are detrimental to mission effectivene ss and lead to increased fatigue of aircraft structures. Previous efforts to suppress limit cycl e oscillations have focused primarily on active control methods. These efforts have been eff ective but require significant measurement and control resources. In this study the investigators test a passive method for suppressing limit cycle behavior. A nonlinear energ y sink, based on the principle of nonlinear energy pumping, is shown to be effective for increasing the stability threshold of a nonlinear two degree of freedom aeroelastic system.