Investigation of compound fault in the Rotor Bearing System with the integration of Central Composite Rotatable Design (CCRD)

This study focuses on investigating the parallel misalignment and surface defects in rotary machines and comprehensive analysis of dynamic models for predictive condition-based maintenance. In this research, dynamic analysis of a rotor-bearing system under parallel misalignment and surface defect faults is conducted for meticulous experimental investigations. A rotor-bearing system test setup has been developed, and faulty conditions were introduced deliberately to record the vibration responses using an FFT analyser at various locations to acquire characteristic frequencies. In an effort to mitigate nonlinear effects, a dynamic model was developed that encompassed operational, geometrical, and material parameters, as well as statistical parameters such as kurtosis and crest factors. The Central Composite Rotatable Design (CCRD) is highly useful for conducting experimental design methods with a comprehensive understanding, while the outcomes are examined using analysis of variance (ANOVA). The amplitude of vibration is most severely affected when defects intersect with the shaft's rotating speed. A significant rise in the amplitude of vibration wasn't observed in the simultaneous occurrence of surface faults and misalignment. Results show that the proposed dimensional analysis model has the ability of fault characteristic frequency prediction and vibration behaviour representation of the parallel misalignment and defective bearing. The precision and dependability of the results are ensured by closely aligning the experimental findings with the predictions made by the model. The dimensional analysis model results also show a reasonable agreement with the experimental values.