Abstract
In this paper we investigate the elastohydrodynamic (EHD) lubrication in ball bearings by means of a digital twin. Based on an original description involving the discrete element method (DEM), the digital twin integrates all the components of ball bearings and enables realistic behavior under mechanical loading and kinematic conditions. In order to check the standard indicators recommended by most ball bearing manufactures, a stiffness model for elliptical Hertzian contact and an improved EHD formulation for lubricated contact are implemented in the numerical tool. In addition, we have introduced into the discrete modeling an electrical capacitance model correlated to the fluid film thickness and the contact pressure. The numerical predictions of lubricant film capacitance provided by digital twin are in good accordance, both qualitatively and quantitatively, with the experimental data available in the literature. The coupling of the discrete method with the electrical approach enables efficient solutions to be provided in terms of lubrication regime in relation to the lubricant properties to optimize the bearing lifetime.
Highlights
Industrial machines require a good lubrication regime with an appropriate lubricant to avoid wear mechanisms that could occur at the contact interface between two surfaces
Several components such as ball bearings, cams and gears operate under EHD lubrication regimes with non-conformal contacts
Throughout this work we have attempted to highlight the relevance of the digital twin when a ball bearing operates under EHD lubrication regimes
Summary
Industrial machines require a good lubrication regime with an appropriate lubricant to avoid wear mechanisms that could occur at the contact interface between two surfaces. With a view to being able to assess whether the machine elements are working with safety conditions or are close to reaching boundary lubrication and ultimate failure, the fluid film thickness is of a prime importance Such mechanical components are often designed for the lubricant film to be thick enough, more than 1 μm, to avoid contact between the mating surfaces ensuring the expected bearing lifetime. The coupling between the mechanical pressure and the dielectric behavior of the lubricant film thickness is carried out by means of the electrical capacitance. According to the model of a two parallel-plate capacitor separated by a dielectric material, the capacitance of the lubricant film thickness is extracted numerically. The electrical capacitance of the lubricant is introduced by means of the parallel-plate capacitor formula depending on the contact pressure and fluid film thickness. We summarize the contributions of this work and we end with a few thoughts on future work
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
