An investigation of dynamic characteristics in rotor-bearing system with combined bearing and coupling defects

The development of comprehensive dynamic model for condition-based maintenance is essential when addressing severe defects, such as misalignment and bearing defects in rotor-bearing system. A dynamic analysis of a rotor-bearing system under angular misalignment and bearing surface defect is presented in this study. Artificial faults are induced in the developed test setup for rotor-bearing system. Vibration responses are collected using an FFT analyzer at various locations, focusing on characteristic frequencies. Additionally, a dynamic model based on a Dimensional Analysis (DA) approach is developed, accounting for operational, geometrical, and material parameters as well as statistical parameters like kurtosis and crest factor to mitigate nonlinear effects. Experimental investigations establish correlation between angular misalignment, surface defect size, and their impact on vibration amplitudes. Notably, the results indicate a strong agreement between the DA model and experimental data, with a negligible error of only 5.62–7%. These findings hold promise for enhancing predictive maintenance in manufacturing industries.