Effect of single- and multi-scale surface patterns on the frictional performance of journal bearings – A numerical study

• Published in: Tribology international 2020-03, Vol.143, p.106041, Article 106041
• Main Authors: König, Florian, Rosenkranz, Andreas, Grützmacher, Philipp G., Mücklich, Frank, Jacobs, Georg
• Format: Article
• Language: English
• Subjects: Asperity; Coefficient of friction; Computer simulation; Design optimization; Direct laser interference laser patterning; Friction reduction; Hot micro-coining; Journal bearings; Lubrication; Mathematical analysis; Mixed-elastohydrodynamic simulation; Multi-scale patterns; Multibody systems; Numerical prediction; Performance prediction; Reynolds equation; Tribology
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2019.106041

The present study aims at numerically predicting the frictional performance of journal bearings with single- and multi-scale surface patterns considering the real 3D surface topographies after wearing-in in mixed-elastohydrodynamic (mixed-EHL) simulations using a multi-body simulation (MBS) environment. For this purpose, the extended Reynolds equation with flow factors according to Patir and Cheng has been combined with a deterministic asperity contact model, which can be further utilized in the design process to optimize the tribological response of engineering systems. For all patterned surfaces, a shift to smaller rotational speeds in the transition from mixed to hydrodynamic lubrication with a notably reduced coefficient of friction has been demonstrated. The largest frictional improvement (- 80%) has been achieved with single-scale surface patterns fabricated by direct laser interference patterning. [Display omitted] •Numerical mixed-EHL simulation of journal bearings considering wearing-in.•Effects of single- and multi-scale surface patterns on journal bearing friction.•Significantly improved friction and wear performance induced by surface patterning.•Maximum friction reduction of 80% has been observed.