Effects of Wall Slip on Hydrodynamic Performances of Water-lubricated Bearings Under Transient Operating Condition

The purpose of this study is to identify the role of the wall slip on the transient hydrodynamic performance of the water-lubricated bearing considering eccentricity rotor. The modified Reynolds equation with the wall slip is used to calculate the transient hydrodynamic pressure, and the motion equation, which is fully coupled with the transient hydrodynamic force, is adopted to determine the journal orbit. The correctness of the present model is verified by the comparisons with the theoretical results in the available literature. Numerical results indicate the unbalance load caused by the eccentricity rotor leads to the transient hydrodynamic, film thickness and slip velocity. Additionally, it is observed that the positive effect of the wall slip on the transient hydrodynamic performance of water-lubricated bearing is highly dependent on the eccentricity ratio, and that the maximum slip velocity is more affected by the slip region compared with the minimum slip velocity. This study is performed to highlight the important role of the wall slip on transient hydrodynamic performance and recommend an optimal wall slip region design under transient operating condition for water-lubricated bearings.