<scp>Dynamic</scp> Response of Faults Cylindrical Bearings Under Starved Lubrication

ABSTRACT The stable operation of cylindrical roller bearings is crucial for the proper functioning of machinery. However, uneven loading of the bearings may lead to roller faults and starved lubrication, which can seriously affect bearing operation. The dynamic mechanism of the bearing is varying greatly with the normal condition. In this study, considering the roller fault and starved lubrication effect, a dynamic model is established through Hertz contact theory and elastohydrodynamic lubrication theory. Then, the evolution of lubricant film thickness in faulty rollers is analysed. Meanwhile, through phase trajectory diagrams, Poincaré diagrams, time‐domain diagrams and frequency‐domain diagrams, the effects of different fault sizes on the bearing vibration are also researched. In addition, the dynamic and lubrication experiment platform is set up, and the experiment data can be obtained. The results show that with the increase of roller faulty sizes, the oil film distribution becomes uneven and the lack of oil becomes more obvious, and nonlinear vibration signals become more complex. Finally, the frequency related to the roller fault frequency in the spectrogram can be clearly identified, such as nf c and mf b ± nf c . The maximum frequency error between simulation and experiment data is 3.8%, and the model accurately describes the fault frequency characteristics caused by roller faults in cylindrical roller bearings.