Vibration Suppression Performance of Parallel Nonlinear Energy Sinks Under Strong Impulse Excitation

Compared to traditional linear vibration absorber (LVA), nonlinear vibration absorber (NVA) has been proved to be more effective in terms of frequency range and/or magnitude of vibration suppression. Nonlinear energy sink (NES) is one representative NVA. Recently, parallel NESs have been investigated by many researchers. However, there is still a lack of study on parallel NESs featuring multistability. To address this gap, this study investigates the vibration suppression capabilities of parallel NESs with tristability introduced by three repulsive magnets (P-3RMNESs) under strong impulse excitation. The dynamic model of the whole system is formulated considering beam rotation and bending, and dipole–dipole model of magnetic force. For a fair comparison, the critical parameters of both the single 3RMNES and P-3RMNESs are optimized using the genetic algorithm. Simulation results reveal that with the same mass, the optimized P-3RMNESs with tristability has better performance compared to the optimized single 3RMNES with tristability. This work provides an approach for designing effective parallel NESs for strong impulse response mitigation.