Vibration Controland Energy Harvesting Of Nonlinear Beam With Nonlinear Energy Sink

Nolinear beams find an increasingly wide in projects.They are extensively applied to aerospace field,such as airfoil with high aspect ratio.Vibration caused by nonliear beams when they work will have negative effects on structures stability and working accuracy,if beams vibrate freely.When vibrational energy from environment can be transferred to electricity as supplementary power,vibration control and energy harvesting could be realized together.Therefore,the study of vibration control and energy harvesting for nonlinear beams is of great significance.This paper presents two designs.One of them is comprised of a nonlinear energy sinks(NES)and a piezoelectric-based vibration energy harvester,the other is the integration of a NES and a giant magnetostrictive material(GMM).Effects of vibration control and energy harvesting of both designs coupled to a nonlinear cantilever are studied.To start off,through Hamilton principle,Galerkin method and Runge-Kutta method,performance of NES couple to a nonlinear beam is better than traditional vibration absorber.Besides,energy dissipated by the damper of NES and harvested by piezoelectric or GMM device is main research subject.Results show that harvesting energy is larger when the value of stiffness and damper of NES is smaller.As the mass of NES or distance between location of device attaching to the beam and free end increases,dissipating and harvesting energy will rise.If the frequency of external excitation equals to the first order natural frequency of the beam,dissipating and harvesting energy by two designs would be maximal.Through Energy Transaction Method(ETM),energy flowing between designs and the nonlinear beam is researched and results show that part of energy is continuously harvested or dissipated by devices in the flowing cycle,which reveal the essence of vibration control.Finally,two designs are proved that they have positive effect on vibration control.To sum up,piezoelectric-NES device and GMM-NES device have abilities to control vibration and harvest energy of the nonlinear beam.