A flow modeling of lubricating greases under shear deformation by cellular automata

Abstract

A Cellular Automata modeling of the lubricating grease flow under the shear deformation is proposed. Lubricating greases are composed of thickening agent, liquid lubricant and various kinds of additives. The thickening agent forms fibrous microstructures in liquid lubricant, and lubricating greases present their special feature due to this microstructure. Though they are widely used in mechanical components, there is little understanding on the lubrication mechanism including the contribution of the fibrous microstructure. There have been proposed no other theoretical model except for the average flow model based on the fluid lubrication theory in tribology field. In the present paper, the flow modeling of lubricating greases under shear deformation was proposed by Cellular Automata, where aggregated thickening agent and liquid lubricant were represented by virtual particles movable on the two-dimensional cell space. It was assumed that the fibrous microstructure was composed of multiple particles, and external stress induces the flow of grease where the particles interacts one another. © Springer-Verlag Berlin Heidelberg 2006.