Mixed-lubrication analysis of misaligned journal bearing considering turbulence and cavitation

By integrating the average flow equation and Ng–Pan turbulence model using the boundary condition of mass conserving [Jakobsson-Floberg-Olsson (JFO)], a mixed lubrication model for misaligned bearing was established considering the effects of turbulence and cavitation. The numerical solution was obtained using a finite difference scheme. The results indicate that the frictional force and moment calculated using the JFO boundary condition are greater than those calculated using the Reynolds boundary condition under the constant external load. In high speed conditions, the turbulence begins to play a role, which makes the maximum oil film pressure and moment decrease and the minimum oil film thickness, cavitation zone, and friction coefficient increase. The boundary condition and turbulence have important effects on the equilibrium position of the axis. The misalignment leads to an obvious increase in the friction of the mixed lubrication area and a slight decrease in that of the hydrodynamic lubrication area.