Evaluation of friction losses in textured hydrodynamic tribo-units of piston machines. Part 1. Overview of modeling techniques

Requirements for efficiency and environmental of internal combustion piston engines (ICE) are increasing every year. Reducing friction losses is one of the promising ways to boost the internal combustion engine and increase the durability of its components. Among the general mechanical friction losses, special attention should be paid to hydrodynamic friction losses of various complexly loaded tribo-units (TU). These units are exposed to high temperature and mechanical stress, variable in time and magnitude. The use of microtexturing of the contacting surfaces allows to reduce the amount of friction losses and prevent “oil starvation”, as well as to increase the bearing capacity of the assembly due to the formation of many “micro wedges”, which contribute to an increase in the reaction of the lubricating layer. The use of texturing affects the formation of zones of divergence and turbulence, which is a poorly studied aspect in the modern literature. The texturing of the crankshaft bearings can be in the form of elliptical micro-dimples of various sizes. This work is presented in two parts. In the first part, special attention is paid to the analysis of scientific sources, methods of mathematical modeling of hydrodynamic phenomena in the lubricating layer. In the second part of the work, the theoretical results of the study will be presented using the example of a connecting rod bearing with different types of texturing of friction surfaces. Initial data will be based on experimental results. Calculations will be carried out in the Ansys Fluent software package and software developed by the authors. The purpose of this article is to consider the current theoretical basis of the physical phenomena and, based on this, the formation of a general algorithm for calculating frictional losses in a radial bearing with texturing.