Abstract： Based on multi-body dynamics, the lubrication calculation model was built for connecting rod big end bearing with consideration of mixed thermoelastohydrodynamic, cavitation and micro-elastohydrodynamic conditions. The method to find cavitation erosion region was proposed, the lubrication state was analyzed, and the heat dissipation of frictional power loss was calculated. The results show that the bearing is in a mixed lubrication state, the asperity contact takes place at both edges of upper bearing top; the cavitation erosion position is recognized by the axis orbit, the lube oil fill ratio, the fill ratio rate of change and the hydrodynamic pressure rate of change; the mean frictional power is 0.44 kW; the maximum transient asperity frictional power is only 111.1 mW, and the monitoring of transient frictional power will not accurately recognize the local lubrication state; and the heat conduction is the main way of energy dissipation in big end bearing lubrication.
Key words：