Simulation Model of a Journal Bearing with a Low-Melting and Porous Coating in the Structure on Different Contact Surfaces

Abstract

The paper is devoted to the development of a simulation model of an infinite radial bearing lubricated with a Newtonian material and a melt of a low-melting metal alloy coating the bearing bushing surface, as well as the shaft surface with a porous coating while considering the pressure dependencies of the lubricant and melt viscosity characteristics and porous coating permeability. Based on an equation describing the motion of a viscous incompressible fluid for the case of a “thin layer”, the continuity equation, the Darcy equation, the equation for the mechanical energy dissipation rate, and the molten contour profile of the bearing bushing while considering the pressure dependencies of the porous coating permeability and the lubricant viscosity, the authors have found an asymptotic solution to a system of differential equations by the parameter K characterizing the melt and the mechanical energy dissipation rate, and the exact self-similar solution for zero approximation without considering the melt and the first approximation considering the melt. As a result, the velocity and pressure fields in the lubricant and porous layers have been determined considering the pressure dependencies of the lubricant viscosity and the porous coating permeability, as well as the function $\mathrm{\Phi}_{1}(\theta)$ characterizing the bearing bushing surface melt. Also, the basic performance characteristics have been determined, i.e. load-bearing capacity and friction force. The authors have also established the effect of the $\mathrm{K},\tilde{H}, \alpha$ , and $\tilde{k}$ parameters characterizing the low-melting metal alloy melt, the porous layer thickness, the pressure dependencies of the lubricant viscosity, and the pressure permeability of the porous layer, respectively, on the bearing capacity and friction force.