Jacobian Free Newton-GMRES Method for Analysing Combined Effects of Surface Roughness and Couple Stress Character of Lubricant on EHL Line Contact

Abstract

Pressure profiles, film shapes and details of Petrusevich pressure spike have been calculated for isothermal, steady and compressible EHL of line contact for moderate to high loads and speeds. The lubricant is a couple stress fluid model and a rough surface is with dents/bumps (local features) and waviness. Governing equations are discretized on uniform grid. For the solution of resulting system of algebraic equations a novel numerical scheme, Jacobian free Newton-GMRES with wavelet based preconditioners, is used. The minimum film thickness increases for larger values of Lm, and couple stress parameter. Pressure spike shrinks and it is of much smaller order (its height as well as spread) for larger values of Lm for moderate values of a , amplitude and l, wavelength respectively.