Multiscale modelling of lubrication between rough surfaces: Application to gas lubrication

Calculating the flow of a film of lubricant between rough surfaces by solving the Reynolds equation requires a very fine mesh to capture the details of the topography and is thus very time consuming. In the present paper, a multiscale method is proposed. The domain is divided into an appropriate number of subdomains on which deterministic simulations are performed. The results of this microscale solution are coupled at the macroscale by employing a macromesh on which a mass flow balance is implemented. This method has already been successfully applied to liquid lubrication and is extended to gas lubrication. A significant reduction in computation time is obtained compared to a fully deterministic solution. The calculation of the load is also accurate.