Suppression of shock vibration by cellular nonlinear energy sinks

Research on nonlinear energy sinks (NESs) typically focuses on vibration suppression under periodic excitations. The influence of NES contact mode on the vibration control performance under shock excitation is studied through theoretical calculation, optimization and experimental verification in this paper. A method for evaluating the vibration control performance under shock excitation is proposed. Firstly, the mechanical model of shock excitation of the linear oscillator coupled with indirect contact NES cells is established. Numerical results show that the vibration control performance of indirect contact NES cells under shock excitation is affected by the natural frequency and excitation intensity. In addition, the additional mass and the layout of the NES will also affect the vibration control performance. The contact damping and contact stiffness under different working conditions can be optimized using the differential evolution algorithm. The experimental results verified the theoretical calculation results. In conclusion, the indirect contact NES cells have excellent vibration control performance under shock excitation with high natural frequency and large initial velocity. This paper provides new ideas for vibration control of shock excitation and evaluation of vibration control performance.