A Numerical Simulation of the Coupling Between Dynamic Behavior and Tribological Behavior in Cylinder-Piston System in IC Engine

A mathematical model for cylinder-piston system considering the coupling between dynamic behavior and tribological behavior is presented in this paper. The three-dimensional finite element method is used to compute the engine block vibrations. The lubrication of cylinder-piston pair was described by an average Reynolds equation considering the piston second-vibration and asperity contact of rough surface. The corresponding computing program developed can be used to calculate the engine block vibrations, the entire piston trajectory, the Piston slap forces, friction forces and oil film thickness etc. as functions of crank angle under engine running conditions. The numerical simulation results show that the coupling between engine block dynamical behavior and lubrication has big influence for the secondary motion of piston and the engine block vibration in cylinder-piston system. It is essential to consider the engine block vibration in the analysis of cylinder-piston tribology.