A Nonlinear Structure Based Elastohydrodynamic Analysis Method for Connecting Rod Big End Bearings of High Performance Engines

Abstract

Big end bearings of connecting rods for high performance automotive engines are quite compliant and exhibit relatively large deformations at high rotation speed. Nowadays numerical simulation provides good estimate of tribological parameters for bearings operating in severe, but not extreme elastohydrodynamic lubrication conditions. At very high rotation speed regimes, reliable previsions are achieved only if an effort to increase the accuracy of structural modeling is accomplished. A finite element model able to account for the nonlinear friction controlled sliding phenomena occurring at the junction surface between the cap and the body of the rod has been developed. A new method to solve the coupled equations governing the interaction between the hydrodynamic fluid model and the nonlinear structural model of the connecting rod bearing is presented, together with a simple application example.