Temperature predication model of floating ring bearing and its experimental validation

Based on nonlinear dynamic oil-film forces, a more precise temperature prediction model of the floating ring bearings of a turbocharger was presented. In this model, the influences of thermal effect on oil viscosity and bearing deformation were considered, and the influences of pressure flow and shear flow on the ring speed ratio (floating ring speed to rotor spin speed ratio) were also taken into account. The oil return flow temperatures measured from experiments were compared with the simulated results. The analysis results indicate that the errors of the model are in an allowable range, verifying the effectiveness of the model. The relationship between oil temperature and rotor spin speed is nearly linear. The variations of temperature, oil viscosity, ring speed ratio and bearing clearance are in reasonable ranges. And the floating ring bearings work well. This would be theoretical foundations for the future R&D and structural optimization of the floating ring bearings.