A Comparison of the Fluid Models Effect on the Internal Stresses of Rough Surfaces

Abstract

A comparison between the effects of Newtonian, hyperbolic, and Eyring fluid models on the internal stresses in EHD lubrication of a smooth and rough stationary surface in contact with a moving smooth surface was obtained. The Newton-Raphson technique was used to solve the simultaneous system of Reynolds and modified elasticity equations. The elasticity equation was modified with the experimental surface measurements obtained from a typical bearing. The pressure and film thickness results obtained from the EHD solution were used to calculate the surface shear stress and the internal stresses. Results have been presented for the dimensionless loads of W = 1.3 × 10−4, 2.3 × 10−4 and speeds of U = 5.46 × 10−11, 1.092 × 10−10 for smooth and rough surface conditions. The results indicate that surface roughness of typical bearings do not significantly affect the depth at which the maximum shear stress occurs.