Ventsel' Е.S., Kravets' A.M. Мathematical model of tribocoupling

Abstract

A mathematical model of the tribocoupling is considered which associates the character of the physical and mechanical processes occurring during the operation with the characteristics of mechanical impurity parti-cles containing in the lubricant l(dispersion degree and concentration). Specific friction force was accepted as a modeled parameter of the tribocoupling. As a result of modeling, friction force and the wear intensity of the tri-bocoupling were associated with dielectric permittivity of the intervening medium. It was found that the degree of dispersion of the impurity particles is primarily determined by a parame-ter of Nukiyama-Tanasawa distribution function. This parameter is growing very strongly with the increase of the degree of dispersion, while the most likely size of the impurity particles does not change significantly. In the resulting model, the specific friction force depends in a complicated way not only on the concen-tration of impurity particles in the lubricant and their sizes, but also on a few other parameters, such as a mini-mum allowed distance from the original particle to the friction surface; "coverage factor"; and the energy of the bound state of dipoles situated on the friction surface. As a result, the analysis of this model requires experimen-tal studies that could provide at least a qualitative estimate of such values, and mainly, determine the influence of the parameters depending on the degree of dispersion of the system on the physical and mechanical processes occurring in the tribocoupling. In general, growing concentrations of impurity particles should, from the theoretical point of view, re-sult in the increase of specific friction force with the low impurity concentrations values and in the decrease with the quite high concentration values. Keywords: trybocoupling, model, specific friction force, impurities, dielectric permittivity