Analysis of Thermal and Surface Roughness Effects on the Performance of Infinitely Long Plane Slider Bearings: Finite Element Methods

Girma, Desu

dc.contributor.author	Girma, Desu
dc.date.accessioned	2026-08-26T08:20:37Z
dc.date.available	2026-08-26T08:20:37Z
dc.date.issued	2024-07
dc.identifier.uri	http://ir.bdu.edu.et/handle/123456789/17079
dc.description.abstract	In this dissertation, the Streamline Upwind Petrov-Galerkin finite element method is used to investigate the performance analysis of slider bearings with the effect of temperature and surface roughness on one-dimensional longitudinal and transverse roughness types. Laminar fluid films, unsteady fluid films with or without heat conduction through the pad and slider, turbulent fluid films with or without porous material, and non-Newtonian power-law fluid-type lubricants were among the fluid lubricants employed in this study. The roughness is thought to have a stochastic and Gaussian random distribution. It is also thought that for a Newtonian fluid lubricant film, viscosity and density depend on temperature. For the purpose of numerical computation, the surface roughness-induced irregularity of the domains is transformed into a regular domain. In addition to the energy equation, the continuity equation and momentum equation are utilised to derive the modified Reynolds equations for each scenario in order to assess the performance of load-carrying capacity and pressure distribution. With appropriate boundary conditions, the approach is connected to the stochastically averaged Reynolds-type equation. The Ng-Pan turbulent model was used to derive the modified Reynolds equation for turbulent lubrication fluid films. In addition, the power-law viscosity model was used to derive the modified Reynolds equation for non-Newtonian lubricant fluid films. The pressure distribution of the combined effects is lower than the thermal and surface roughness effects in the case of the one-dimensional longitudinal surface roughness model for non-parallel slider bearings (w = 0.4). However, the thermal effect is less than the combined and surface roughness effect for the one-dimensional transverse surface roughness model type. In an unsteady state with heat conduction through the solid, the bearing performance under isothermal boundary conditions is superior to that of adiabatic and exposed boundary conditions to the environment. Furthermore, we also look at the combined effect at different temperatures. As a result, for both models, a higher slider temperature than the pad temperature improves load-carrying capacity performance. A one-dimensional longitudinal surface roughness slider bearing typically has a lower pressure distribution than a one-dimensional transversal surface roughness model type. In general, taking the surface roughness effect, inertial effect, turbulent lubrication effect, the porous permeability parameter, and non-Newtonian power-law fluid properties will typically improve the bearing performance of infinitely long plane slider-bearing. The numerically obtained results were presented using tables and graphs. vi	en_US
dc.language.iso	en_US	en_US
dc.subject	Mathematics	en_US
dc.title	Analysis of Thermal and Surface Roughness Effects on the Performance of Infinitely Long Plane Slider Bearings: Finite Element Methods	en_US
dc.type	Dissartation	en_US