Hydrodynamic lubrication of a two-piece piston skirt considering deformations

The main development directions in modern power engineering industries are related to increasing the output power and improving the economic and ecological performance of the engine. The group of pistons inside the engine highly affects the reliability of the reciprocating engine and its power and economic performance. This paper presents a mathematical model developed by the authors to calculate the hydrodynamic characteristics of the oil layer, taking into account the transverse motion of a two-piece piston, piston skirt deformations and variable viscosity of the lubricant in the interface. The conducted research is aimed at developing a piston design that will provide liquid friction in the piston skirt-cylinder junction during the entire operation cycle. Particular attention is paid to the evaluation of the accuracy of the obtained results. The results of the study of the computational mesh size in the numerical solution of the elastic-hydrodynamic problem on the accuracy of calculation of the hydrodynamic characteristics of the oil layer in the piston skirt-cylinder junction considering the piston skirt deformations are presented. This paper provides an example on studying the influence of the piston skirt profile on the hydrodynamic characteristics of the oil layer and the lateral movement of the piston skirt. The calculations were carried out using program codes developed by the authors. © 2021 Author(s).