Numerical study on transient response suppression performance of a clutch inerter nonlinear energy sink

The effectiveness of traditional cubic nonlinear energy sinks (CNESs) in suppressing vibration responses is highly dependent on the amplitude of external excitation, limiting their robustness in practical applications. To address this limitation, this study proposes a novel clutch inerter nonlinear energy sink (CINES) concept device, which operates in two distinct states and enables unidirectional energy absorption and dissipation. The equations of motion of the CINES for suppressing the transient response of a single-degree-of-freedom (SDOF) oscillator are established. To optimize the design parameters of the CINES, the particle swarm optimization (PSO) algorithm is employed. The vibration response suppression performance of the CINES is systematically evaluated and compared against an optimal CNES under impulsive loads. The effects of inerter ratio, stiffness ratio, mass ratio, and damping of the CINES on response suppression performance are analyzed. Finally, the real-world comparative performance of the CINES and CNES is assessed under various representative seismic excitations. The results indicate that the CINES facilitates enhanced energy dissipation performance equivalent or better to that of the CNES. Furthermore, the effectiveness of CINES in suppressing vibration responses is shown entirely immune to external excitation amplitude. These characteristics highlight the superior robustness and broader applicability of the CINES compared with the CNES, particularly in practical engineering scenarios involving random excitation conditions.