Matching design for structural parameters of the dual-friction pair in a piston pin

In the present study, a thermoelastic hydrodynamic (TEH) model was formulated to analyze the steel piston assembly in the D25TCIF diesel engine. The model facilitated the evaluation of the steel piston and connecting rod assembly by integrating elastohydrodynamic lubrication theory and heat transfer analysis. The influence of bearing structural parameters on the lubrication performance of the piston pin bearing system was analyzed by integrating experimental design with the Pareto multi-objective optimization algorithm. Subsequently, an optimized structural parameter design was explored to achieve a balanced lubrication performance within the piston pin bearing system. The results demonstrated that, compared to the original engine design, the oil film thickness of the pin bore bearing increased by 177.68 % (0.629 μm), while that of the small-end bearing of the connecting rod increased by 24.21 % (0.145 μm). Therefore, the proposed optimization method demonstrated significant effectiveness in enhancing lubrication performance.