CFD Investigation of Reynolds Flow around a Solid Obstacle

Abstract

The Reynolds equation defines the lubrication flow between the smooth contacting parts. However, it is questionable that the equation can accurately anticipate pressure behavior involving undeformed solid asperity interactions that can occur under severe operating conditions. Perhaps, the mathematical model is inaccurate and incomplete, or some HL (hydrodynamic lubrication) and EHL (elastohydrodynamic lubrication) assumptions are invalid in the mixed lubrication region. In addition, the asperity contact boundary conditions may not have been properly defined to address the issue. Such a situation motivated the recent study of a 3D CFD investigation of Reynolds flow around the solid obstacle modelled in between the converging wedge. The produced results have been compared to analytical and numerical results obtained by employing the Reynolds equation. The validated CFD simulation is compared with the identical wedge, with cylindrical asperity at the center. A significant increase in pressure has been predicted because of asperity contact. The current study shows that the mathematical formulation of the ML problem has shortcomings. This necessitates the development of a new model that can also include fluid flow around asperity contacts for the accurate prediction of generated pressure. Consequently, sustainable tribological solutions for extreme loading conditions can be devised to improve efficiency and component performance.

Keywords

• mixed lubrication (ML)
• computational fluid dynamics (CFD)
• numerical simulation