Suppressing Flow-Induced Vibrations by Parametric Excitation

The possibility of suppressing self-excited vibrations of mechanicalsystems using parametric excitation is discussed. We consider a two-masssystem of which the main mass is excited by a flow-induced, self excitedforce. A single mass which acts as a dynamic absorber is attached to themain mass and, by varying the stiffness between the main mass and theabsorber mass, represents a parametric excitation. It turns out that forcertain parameter ranges full vibration cancellation is possible. Usingthe averaging method the fully non-linear system is investigatedproducing as non-trivial solutions stable periodic solutions and tori.In the case of a small absorber mass we have to carry out a second-ordercalculation.