Chiral metamaterial -inerter nonlinear energy sink for torsional vibration suppression of the rotor system

This paper explores the use of a chiral metamaterial inerter nonlinear energy sink (CINES) for suppressing torsional vibrations in a rotor system. The compress-torsion coupling effect of the chiral metamaterial is adopted to construct the inerter amplification mechanism, which is then combined with the NES to form CINES. The dynamic model of the rotor-CINES coupled system is established, the transient torsional vibrations and steady-state torsional vibrations are optimized by genetic algorithm and the optimal parameters for numerical simulation are obtained. Then, the vibration suppression capability of CINES is evaluated. Moreover, experiments on the CINES are carried out to verify the theoretical results. The results show that the cumulative energy dissipation rate of CINES in transient torsional vibration suppression can reach 89.2 %, and the percentage of vibration suppression in steady-state torsional vibration suppression can reach 88.5 %. Furthermore, the CINES saves more than 10 times its moment of inertia while achieving the same vibration reduction ratio.