Effect of Al₂O₃ nanoparticle additives on the performance characteristics of rough journal bearings

Abstract

Abstract This paper investigates the influence of Al 2 O 3 nanoparticle additives on static and dynamic characteristics of water-lubricated rough journal bearings under thermo-hydrodynamic lubrication (THL). The time-dependent modified Reynolds equation and the approximated adiabatic energy equation have been formulated and solved numerically with boundary conditions and initial conditions. The results are presented for dimensionless maximum film pressure, dimensionless maximum film temperature, dimensionless minimum film thickness, eccentricity ratio, attitude angle, dimensionless friction force, spring constants, damping coefficients and mass parameters for both journal bearings with transverse roughness patterns and with longitudinal roughness patterns under a dimensionless load of 7. The results show that journal bearings with Al 2 O 3 nanoparticle additives tend to significantly increase load carrying capacity and minimum film thickness by decreasing both the eccentricity ratio and temperature rise for longitudinal roughness patterns. For journal bearings with longitudinal roughness patterns and lubricated with Al 2 O 3 nanoparticle additives, the stability region tends to increase.