DNS of Turbulent Channel Flow in the Presence of a Thin Liquid Film

Abstract

The effect of a thin liquid film between the bulk flow and one of the walls of a plane channel is investigated by means of DNS. Even though the turbulent activity is reduced within the highly viscous film, the velocity fluctuations in the bulk fluid are more intense adjacent to the film-bulkfluid interface than in the absence of the liquid film. Near-wall coherent structures are generally smaller on the film-side, as compared to the dry side of the channel where the structures are similar in size to those of a conventional channel flow.