Investigations on transitions of lubrication states for water lubricated bearing. Part I: determination of friction coefficients and film thickness ratios

Abstract

Purpose This paper aims to provide efficient methods to calculate the friction coefficients and film thickness ratios in mixed lubrication (ML) regime for water lubricated bearings. Mathematical models consider influence of micro-asperities contacts which is based on the Gauss random distribution. Design/methodology/approach Effects of external loads, rotating speeds and radial clearances are obtained. Algorithm shown here is applied to a class of common industrial problems. Calculated Stribeck values are given and evaluated. The calculated and experimental results agree well which proves the correctness of the model. Findings In Part I, the authors believe that the paper presents the following for the first time: universal methods are developed for the calculation of friction coefficients and film thickness ratios (lambda) in ML regime; effects of different external loads, rotating speeds and radial clearances on friction coefficients and film thickness ratios are presented in detail; comparisons are made between the results predicted by the model and experimental results, and they agree rather well which proves the correctness of the model. Originality/value Present work successfully develops universal methods for predicting the friction coefficients and film thickness ratios.

A Numerical Model for the Analysis of the Bearings of a Diesel Engine Subjected to Conditions of Wear and Misalignment

“…where F x and F y are the forces applied in the x-y direction, M j is the mass of the journal, and F oil x and F oil y are the reaction forces of the lubricating oil. The equations of motion are described by Equations ( 30) and (31). The lubricating oil forces F oil x , F oil y and the components of the moments M x , M y are determined by the following equations:…”

“…Xie et al [27] studied the performance of water lubrication and dynamic characteristics in bearings with misalignment using CFD. In addition, the different lubrication regimes were evaluated, such as limit, mixed, and hydrodynamic lubrication [28][29][30][31][32].…”

Effect of Surface Topography and Structural Parameters on the Lubrication Performance of a Water-Lubricated Bearing: Theoretical and Experimental Study

“…The measuring accuracy of the force sensor was 0. values fluctuate periodically with time with a small amplitude. A more detailed description of the test bearing can be found in the reference [34,35]. Figure 6a-d shows the 3D morphology distribution of the four test bearings.…”

“…This occurred because of the existence of the circumferential grooves and the surface topography. Xie et al [34][35][36] explored the lubrication states, lubrication performance with consideration of the bushing macro deformation using theoretical simulation and experimental verification. Their results indicated that the surface roughness had a significant influence on the lubrication state transition and the lubrication performance.…”

Numerical study on the dynamic characteristics of water-lubricated rubber bearing under asperity contact

“…Many scholars studied the steady lubrication performances, numerically and experimentally, of the water-lubricated bearing (Wang et al, 2014;Xie et al, 2016;Zhao and Zhang, 2020). In the mentioned literature, the water hydrodynamic pressure was determined by general (Wang et al, 2014;Zhao and Zhang, 2020) or average Reynolds equation, the bush deformation was calculated by the Boussinesq method (Wang et al, 2014;Xie et al, 2016;Zhao and Zhang, 2020) and the asperity contact pressure was simulated by Bowden model (Bowden and Tabor, 2001). However, Meng and Chen (2015) proved that the Boussinesq method was effective for journal bearings only when the eccentricity ratio was relatively small.…”