Thin Film Hydrodynamic Bearing Analysis Using Nanoparticle Additive Lubricants

Abstract

Analysis of thin film lubrication of (i) nanoparticle additive three-layered journal bearing lubricated with Newtonian fluid, (ii) nanoparticle additive three-layered journal bearing lubricated with couple stress fluid, (iii) Newtonian fluid lubricated partial slip slider bearing with electric double layer, and (iv) porous-layered carbon nanotubes (CNTs) additive Newtonian fluid lubricated slider bearing with electric double layer are presented. The analysis of three-layered journal bearing with nanoparticle additives incorporates Reynolds boundary conditions to predict load capacity parameter and coefficient of friction. The load capacity parameter increases for thick, high-viscosity fluid film layers and nanoparticle additive fluid film. Coefficient of friction is reduced for high viscosity surface adjoining layer. Stokes microcontinuum theory is used in the analysis of couple stress fluids in a three-layered journal bearing lubricated with nanoparticle additives. A three-layered journal bearing using couple stresses fluids with nanoparticle additives increases nondimensional load capacity and decreases coefficient of friction. A slider bearing with partial boundary slip and electric double layer leads to an increase in apparent viscosity of lubricant and hence load carrying capacity in thin film lubrication. A parallel slider bearing with partial slip on bearing and electric double layer increases the bearing load capacity. The flow of lubricant with CNT additives in a slider bearing in thin film and porous layers with electric double layer is governed by Stokes and Brinkman equations, respectively, including electrokinetic force. The nondimensional load capacity of slider bearing increases with decrease in permeability and increase in thickness of porous layer as well as increase in both electro-viscosity and CNT additives volume fraction. A thin film slider bearing using CNT additive lubricants with porous and electric double layer provides higher load capacity.