Computational Analysis of Wall Slip and Cavitation in Lubricated Sliding Systems

Abstract

Lubrication is applied to systems in which parts are in relative motion to avoid direct contact between the surfaces. The behavior of the fluid-film in sliding bearings depends on the boundary conditions at the interface between the liquid and the surfaces. Many researchers have found that wall slip may occur on specially engineered surfaces. A modified Reynolds equation with slip boundary conditions is proposed. This paper shows the performance of hydrodynamic lubrication in flat sliding bearing contacts in for instance MEMS (Micro Electro Mechanical System) using a slip surface. Parameters such as the slope incline ratio, slip length, and slip area are used to calculate the load support and friction. The wall slip is based on the Navier relation. The modified Reynolds equation is discretized by finite volume methods and solved by the Tridiagonal Matrix Algoritma (TDMA). The occurrence of cavitation phenomena is modeled using the Half-Sommerfeld approach. Results show that applying slip and the cavitation condition may increases the performance of sliding lubricated contacts.