Fault Analysis of Journal Bearing Considering the Turbulent and Thermo-Hydrodynamic Effects

In order to investigate the cause of the typical bush rupture and wear damages in the journal bearing of the steam turbine generator set, the lubrication turbulence and thermo-hydrodynamic effects were studied. The generalized Reynolds equation, energy equation and heat conduction equations were solved with the finite difference method, and the pressure, temperature, thickness distribution of the oil film were obtained. Analysis results can be well explains the bearing bush burst in bearings maximum pressure place because of heavy load running. The bearing bush burst made friction intensified that caused oil temperature increasing and the viscosity reduce, which led to the rotor eccentricity increase, the minimum film thickness smaller and bearing static working point down, thus causing the wear damages until shutdown.