Nonlinear energy sink with combined nonlinearities: Enhanced mitigation of vibrations and amplitude locking phenomenon

摘要

The paper considers dynamic response of primary linear oscillator with nonlinear energy sink (NES) that comprises purely cubic oscillator with internal rotator. It is demonstrated that this NES exhibits enhanced mitigation capabilities and, in particular, remains efficient for much broader range of initial energies as compared to regular cubic NES with the same mass. This enhanced performance is related to very special response regime revealed in detached cubic-rotatory NES and referred to as amplitude locking. In this regime, the amplitude of the oscillator remains independent on frequency of the system for very broad frequency range. This phenomenon is explored analytically and numerically, and possible applications are discussed.