Effect of transverse surface roughness and additives in TEHD contacts

Surface roughness effects in mixed rheological thermal EHL of rolling/sliding line contacts are investigated numerically. The surface roughness is assumed to be transverse and its profile is generated by a sinusoidal function defined in terms of its amplitude and wavelength. A homogeneous mixture of Newtonian base oil and power law fluid additive with varying volume fraction, viscosity ratio and power law index is used to represent polymer-modified oils. The velocity profile for the mixed rheological fluid model is obtained using perturbation method to derive Reynolds and mean temperature equations. It is found that the surface roughness effects on EHL characteristics are significantly modified due to the presence of polymeric fluid additives.