Rapid calculation of the pressures and clearances in rough, rolling-sliding elastohydrodynamically lubricated contacts. Part 2: General, non-sinusoidal roughness

Abstract

Part 1 of this paper [1] described how the behaviour of low amplitude, sinusoidal roughness in elastohydrodynamically lubricated (EHL) contacts could be characterized by three complex quantities: attenuation of original profile, amplitude of complementary wave and its wave number and decay rate. This second part outlines how these results can be used to estimate, rapidly, the clearances and pressures in any rough EHL contact. The method is applied to a number of contacts for which accurate experimental results are available and it is shown that the process gives close estimates of the clearance and pressure distributions where the amplitude of the attenuated roughness is less than 50 per cent of the clearance and good indication of the behaviour of rougher surfaces.

Two-scale EHL: Three-dimensional topography in tilted-pad bearings

“…Because deformation is linear the result can be scaled directly to match the required large scale local stiffness, resulting in Eq. (7). In order to model the required load per unit area derived from small scale simulations Eq.…”

“…The potential of topographical features to improve bearing performance has increased the importance of surface roughness and texturing within bearing design [4]. A number of authors have sought solutions to the Reynolds equation which fully resolve lubrication flow at both the scale of topography and that of the bearing contact region [5][6][7][8].A s topographical features become more important flow analyses based on solutions of the Stokes or Navier-Stokes equations have been shown to be more accurate than those based on the traditional Reynolds equation [9].…”

Contact fatigue initiation and tensile surface stresses at a point asperity which passes an elastohydrodynamic contact

“…Jiang et al [40] and Deolaliker [41] et al studied the contact pressure and temperature increase due to asperities passing through the EHL contacts. Hooke et al [42] presents a new numerical set-up for EHL simulation including asperities. Li and Kahraman did also look into fatigue caused by the roughness but instead with the fatigue model proposed by Liu and Mahadevan [43].…”

Roughness in soft elastohydrodynamically lubricated contacts – Attenuation and the complementary wave reassessed

“…Most of the results presented will be for sinusoidal roughness although that roughness may be inclined to the contact. However, using Fourier transform methods 18,19 it is possible to examine more general profiles and a few results of this type will be given. Finally, only fully flooded conjunctions will be considered although extension to starved conditions is straightforward.…”