Piezoviscous effects in nonconformal contacts lubricated hydrodynamically

The analysis in this Paper is concerned with the piezoviscous-rigid regime of lubrication for the general case of elliptical contacts. In this regime, several, formulas of the lubricant film thickness have been proposed. However, either the load parameter W is not included, which has a strong effect on film thickness, or the film thickness is overestimated by using the Barus formula for pressure viscosity characteristics. In the current study, the Roelands formula has been used for the pressure-viscosity relationship. The effects of the dimensionless load, speed, and materials parameters, the radius ratio, and the lubricant entrainment direction have been investigated. Forty-one cases were used in obtaining the minimum film thickness formula: H₀ = 178G^0.386U^1.266W^−0.880 (1 − e^−0.0387α Contour Plots indicate in detail the pressure developed between the contacting solids.