Friction-induced vibration and noise of marine stern tube bearings considering perturbations of the stochastic rough surface

• Published in: Tribology international Vol. 131; pp. 661 - 671
• Main Authors: Lin, Chang-Gang, Zou, Ming-Song, Sima, Can, Liu, Shu-Xiao, Jiang, Ling-Wen
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.03.2019; Elsevier BV
• Subjects: Bearings; Coefficient of friction; Degrees of freedom; Eigenvalues; Equations of motion; Fast Fourier transformations; Fourier transforms; Friction; Mode-coupling; Noise; Peak frequency; Resonant frequencies; Rough surface; Stability analysis; Steel plates; Sterntubes; Stiffness; Time dependence; Vibration; Vibration; Rough surface; Friction; Noise; Mode-coupling
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2018.11.026

To investigate the mechanism of friction-induced vibration and noise of marine stern tube bearings, a three-degree-of-freedom (3-DOF) mode-coupling model considering perturbations of the stochastic rough surface is proposed. Perturbations of the stochastic rough surface are modeled as a time-dependent displacement which can be obtained by the inverse fast Fourier transform (IFFT) based on an assumed power spectrum density (PSD). The stability characteristics of the 3-DOF system are studied through complex eigenvalue analysis, and the vibrational responses are determined by solving the equations of motion with the Newmark method. Results show that the friction coefficient and the contact stiffness have a significant effect on the stability of the system. The stochastic rough surface is equivalent to an excitation source in the friction-induced vibration and noise system. The peak frequencies of the friction-induced vibration and noise are determined by the natural frequencies of the system. A new phenomenon is found that the magnification of vibration will occur when two mode frequencies get close to each other, even the system is stable. This phenomenon is validated through a friction-induced noise experiment of the steel plates in the air. This work focuses on more fundamental study on the mechanism of friction-induced vibration and noise of marine stern tube bearings. The novelty of this work is this newly proposed mechanism model which provides a new perspective for the study of friction-induced vibration and noise of marine stern tube bearings. •A three-degree-of-freedom mode-coupling model considering perturbations of the stochastic rough surface is proposed.•The magnification of vibration will occur when two mode frequencies get close to each other, even the system is stable.•The relevant conclusions are validated through a friction-induced noise experiment of two steel plates in the air.•The model presented in this work provides a new perspective for the study of friction-induced vibration and noise.