Study on coupling transient mixed lubrication and time-varying wear of main bearing in actual operation of low-speed diesel engine

• Published in: Tribology international 2024-03, Vol.191, p.109159, Article 109159
• Main Authors: Chen, Rui, Zhao, Bin, He, Tao, Tu, Liyue, Xie, Zhongliang, Zhong, Ning, Zou, Dequan
• Format: Article
• Language: English
• Subjects: Fatigue damage; Main bearing of low speed engine; Mixed elastohydrodynamic lubrication; Wear
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2023.109159

In order to investigate the interaction effect between the transient wear behavior and the lubrication characteristics of the main bearing in low-speed diesel engine under the actual working condition, a coupling model of mixed elastohydrodynamic transient lubrication and time-varying wear is constructed. The transient lubrication model considering the journal misalignment and elastic-plastic asperity contact is used to consider the lubrication characteristics of the main bearing. The wear mechanism of the main bearing material (Babbitt alloy) is found to be surface fatigue wear mainly by the experiments under the equivalent lubrication state, thus the wear model is based on the fatigue damage theory. Several experiments were conducted to verify the accuracy of the coupled model. It is found that the wear gradually increases with increases with wear time, and meanwhile, the lubrication characteristics also change with the wear status. In addition, the effect of the parameters including radius clearance, rotation speed, journal misalignment and bearing loads on the properties of lubrication and wear were investigated. This work would provide practical support for the investigation of wear and lubrication behavior under actual low-speed diesel engine operation. •A coupling analysis model of mixed elastohydrodynamic transient lubrication and time-varying wear of the main bearing under actual dynamic load was established.•The wear mechanism of the main bearing material is found to be surface fatigue wear mainly by the experiments under the equivalent lubrication state of actual condition in low-speed diesel engine.•The verifications of axis orbit, friction coefficient and wear depth indicate the accuracy of the coupling model.•The improvement of bearing lubrication performance after stable wear under actual working conditions was revealed.