Energy Pumping of Mechanical Oscillators in an Array Configuration Under Impulse and Parametric Excitation

We study the classical form of a nonlinear energy sink (NES) in a vibrating system that consists of weakly coupled, damped oscillators in a multi-DOF array. The energy pumping is unidirectional, i.e., absorbs vibrational energy from the linear to nonlinear oscillator. The robustness of the energy pumping towards NES is investigated by separately introducing nonlinearity as a Duffing and van der Pol term in the NES oscillator. The energy transfer towards NES is computed from the amplitude equations of the oscillators’ derived using the method of averaging. The model is tested under both impulse and parametric excitations. We also investigate the vibration suppression in the array under the influence of a slight frequency mismatch between NES and other linear oscillators. Furthermore, we put forward the possibility of a two-way spatial energy pumping by reorganizing the coupled oscillators in a closed loop.