A Novel Numerical Approach to Investigate Shaft Diameter Effect on Dynamic Behaviour of Multi-Disc Rotors

In this study, a displacement-based finite element model was developed to investigate the effect of the diameter of rotating shafts on dynamic performance of a multi-disc rotor system with respect to their natural frequencies and critical speeds. The variation in rotor bearing stiffness was considered in this study. A numerical case study that simulating a typical rotating machine was adopted to assess the present methodology. The results obtained show that the diameter of the rotor has a significant effect on the rotor dynamic characteristics. The amount of the influence was found to be highly sensitive to bearing stiffness of the rotating machine. An experimental setup was constructed and tests were performed to validate the applicability of the numerical model. The reasonable agreement found between the results obtained numerically and experimentally validates the proposed numerical model.