A piston tribodynamic model with deterministic consideration of skirt surface grooves

The machining micro-grooves on the piston skirt surface are very common in internal combustion engines. To accurately investigate the influence of the grooves on piston tribodynamic performance, a coupling model of piston skirt-liner lubrication and crank-rod-piston multibody dynamics is built in this study. The lubrication model is solved by the Finite Element Method with deterministic treatment of the grooves. The multibody dynamics equations are formulated with Lagrange multipliers and constraint Jacobian matrix in the form of Differential Algebraic Equations (DAEs). The MEBDF approach is applied to a high efficient time integration of the DAEs. Based on the above model, the influences of grooves and some groove parameters on piston skirt liner lubrication as well as piston slap are studied and revealed.