The dynamic model of lubricating layer formation/destruction processes in boundary and mixed friction modes

Don State Technical University, 1, Gagarin Sq., 344002 Rostov-on-Don, Russia

Abstract

The article is dedicated to studies of self-organization processes evolving in time in boundary lubricant layers. The essence of the article consists in use of the model of the connected processes of formation and destruction of a shielding delayed lubricant layer based on differential equations similar to that which are used for description in time of dynamics of probabilities of states of a single channel system of queueing theory with Poisson stream of queries and exponential service (Kolmogorov-Chapman equations). Proposed method involves introducing concepts: the intensity of delayed layer growth - l and the intensity of delayed layer destruction - m. This kind of concepts, in author’s opinion, is organically inherent in atomic-scale molecular systems consisting of large numbers of particles with many significant connections between them, all of which are impossible to describe and simulate. The studies of lubricating layers formation/destruction processes and structure of boundary lubricant layers in the medium of paraffin oil as a lubricant at different sliding speeds and loads were made. It was established that minimal values of friction coefficient were characteristic for layers with high intensity of delayed layer growth and high values of limit thickness. Proposed approach to modeling phenomena of self-organization in boundary lubricant layer can be useful for understanding the mechanism of lubricating action in conditions of boundary and mixed friction and applied for solving some practical problems related to the selection of effective lubricants for tribo couplings of the specified configuration and loading parameters.