CFD simulation of elastohydrodynamic lubrication problems with reduced order models for fluid–structure interaction

Abstract

Recently, simulations of elastohydrodynamic lubrication (EHL) problems based on a coupled solution of the Navier–Stokes equations and solid mechanics have been presented. Compared to classical approaches in EHL, however, the simulation time is significantly higher. In this work, the elastic solids are represented by reduced finite element (FE) models in order to decrease the calculation time while keeping the possibility to simulate complex geometries and materials. To eliminate the necessity of matching meshes at the fluid–solid interface, an interpolation method based on radial basis functions is applied to an EHL line contact. By using this energy-conserving interpolation, the number of solid interface points is reduced by a factor of four compared to the fluid interface points with approximately identical pressure and film thickness profiles. Hence, the memory size of the FE matrices can be reduced by more than 90%, leading to an efficient deformation calculation even for complex solids.

Keywords:

• Elastohydrodynamic lubrication
• Reduced order models
• Radial basis function interpolation
• Non-conformal meshes
• Fluid–structure interaction
• Computational fluid dynamics
• Reduced finite element models
• Navier–Stokes equations