A general tribo-dynamic model for lubricated clearance joints in spatial multibody systems

Existing tribo-dynamic models encounter challenges in accurately characterizing the intense coupling and notable nonlinearity between component deformation and oil film pressure in lubricated clearance joints. Consequently, a novel general tribo-dynamic coupling model based on an absolute coordinate framework has been developed in this paper. The equations of motion for flexible multibody systems are formulated based on the absolute nodal coordinate formulation. Mixed lubrication equations are defined at spatial nodes on reference surfaces by employing the mixed Eulerian-Lagrangian approach. The model is applied to a translational clearance joint, validated through an impact test rig. Comparing the dynamical response signals from the model and experiment demonstrates its accuracy in depicting the strong coupling characteristics between deformation and pressure fields in lubricated clearance joints.