Nonlinear dynamic analysis of multiple grooved water-lubricated journal bearings using attenuation rate interpolation method. Issue 10 (23rd November 2021)

• Record Type: Journal Article
• Authors: Li, Qiang; Liu, Qinglei; Wang, Yujun; Zhang, Shuo; Du, Yujing; Li, Bin; Xu, Wei-Wei
• Is Part Of: Industrial lubrication and tribology. Volume 73:Issue 10(2021)
• Page Start: 1342
• Page End: 1351
• Publication Date: 2021-11-23
• Subjects: Water-lubricated journal bearings -- Computational fluid dynamics (CFD) -- Grooves -- Instability -- Nonlinear effect; Lubrication and lubricants -- Periodicals; Tribology -- Periodicals; 621.89
• DOI: 10.1108/ILT-04-2021-0131
• Languages: English
• ISSNs: 0036-8792

Abstract

Abstract : Purpose: The stringent requirements for environmental protection have induced the extensive applications of water-lubricated journal bearings in marine propulsion. The nonlinear dynamic analysis of multiple grooved water-lubricated bearings (MGWJBs) has not been fully covered so far in the literature. This study aims to conduct the nonlinear dynamic analysis of the instability for MGWJBs. Design/methodology/approach: An attenuation rate interpolation method is proposed for the determination of the critical instability speed. Based on a structured mesh movement algorithm, the transient hydrodynamic force model of MGWJBs is set up. Furthermore, the parameters' analysis of nonlinear instability for MGWJBs is conducted. The minimum water film thickness, side leakage, friction torque and power loss of friction are fully analyzed. Findings: With the increase of speed, the journal orbits come across the steady state equilibrium motion, sub-harmonic motion and limit circle motion successively. At the limit circle motion stage, the orbits are much larger than that of steady state equilibrium and sub-harmonic motion. The critical instability speed increases when the spiral angle decreases or the groove angle increases. The minimum water film thickness peak is at the rotor speed of 4, 000 r/min for the MGWJB with Sa = 0°. As rotor speed increases, the side leakage decreases slightly while the friction torque and the power loss of friction increase gradually. Originality/value: Present research provides a beneficial reference for the dynamic mechanism analysis and design of MGWJBs.