Dynamic of a Flexible Rotor-Bearing System Supported by Worn Tilting Journal Bearings Experiencing Rub-Impact

Abstract

Wear usually occurs in the loaded part of hydrodynamic bearings and leads to bearing geometry imperfections. This paper investigates the effects of wear-induced geometric imperfections of tilting pad journal bearings (TPJBs) on the dynamic behavior of the system. Furthermore, the effect of wear on the journal-bearing rub-induced contact pressure severity is investigated. A novel tribo-dynamic model is proposed for a flexible rotor-worn TPJB which integrates a mixed elastohydrodynamic model with a rotor-worn TPJB thermal and dynamic model to assess the effects of the bearing wear progression on rotor-TPJB behavior. Based on the results, wear changes the temperature distribution of the pads and oil film as well as the dynamic behavior of the system. Dynamic simulations reveal a higher vibration level and contact pressure for the worn TPJBs near the system’s critical speed and service speed. Finally, thermal and dynamic condition indicators are suggested to detect TPJB wear severity at its early stages.

An Intelligent Diagnostic Method for Wear Depth of Sliding Bearings Based on MGCNN

“…For sliding bearings, current research mainly focuses on issues such as rotor stability [20][21][22][23][24][25][26][27], calculation of oil film stiffness and damping [28][29][30][31], as well as material wear resistance performance [32][33][34], aiming to enhance the lubrication performance and wear resistance of bearings at the design stage. Although improving the lubrication performance and wear resistance of sliding bearings can effectively alleviate material wear problems, wear is inevitable during equipment startup, shutdown stages, and under the influence of some unexpected factors [35].…”

Digital Twin-Driven Lifecycle Management for Motorized Spindle

“…With the increase of the wear capacity, the bearing wear will experience three periods that are the rapid increasing, steady increasing, and constant [3]. Tofighi-Niaki et al [4] investigated the effects of wear-induced geometric imperfections of tilting pad journal bearings on the dynamic behavior of the system and suggested to detect the thermal and dynamic condition to monitor the wear severity at its early stages. Alves et al [5] analyzed the vibration behavior in presence of bearing wear and used the spectral analysis to understand intact and worn bearing characteristics for identifying the wear severity.…”