%0 Journal Article
%A Srirattayawong, Sutthinan
%A Gao, S.
%D 2013
%I Begell House
%K elastohydrodynamic, surface roughness, lubrication, Newtonian
%N 3
%P 195-213
%R 10.1615/ComputThermalScien.2013006347
%T A COMPUTATIONAL FLUID DYNAMICS STUDY OF ELASTOHYDRODYNAMIC LUBRICATION LINE CONTACT PROBLEM WITH CONSIDERATION OF SURFACE ROUGHNESS
%U http://dl.begellhouse.com/journals/648192910890cd0e,2e2d35a1125a6cd1,175120ef7c1a8cb5.html
%V 5
%X Traditionally, the Reynolds equation is widely used to describe the flow of lubricants for the elastohydrodynamic lubrication (EHL) problem, though there are a number of limitations for this approach. In this work an advanced computational fluid dynamics (CFD) model has been developed for such EHL problem. The CFD model developed can predict the characteristics of fluid flow in the EHL problem, taking into consideration the pressure distribution, minimal film thickness, viscosity, and density changes. The cylinder is considered to be an elastic deformation which is a function of the generated
pressure and the elasticity of the material. Above all, the surface of the cylinder is defined to have an arbitrary
roughness, though only the cases with moderate roughness are reported in this paper. Reconstructing the object geometry, meshing and calculation of the conservation of mass and momentum equations are carried out by using the
commercial software packages ICEMCFD and ANSYS Fluent. In addition, the user-defined functions for density, viscosity, and elastic deformation of the cylinder as the function of pressure need to be defined for this particular work. A number of simulation cases have been investigated, and detailed results of velocity, pressure distribution, and film thickness are obtained. In particular, the effects of surface roughness on the EHL line contact problem are compared to the smooth surface case when the applied load is varied. It is found that the pressure profile at the center of the contact area
directly relates to the roughness amplitude and the applied load. The surface roughness influences the fluctuated shape of pressure distribution. The pressure and the effect of surface roughness increase when the applied load is increased.
%8 2013-04-23