On the flow of a thin liquid film over a rough rotating disk

Abstract

This study addresses the depletion of thin liquid films due to centrifugation. Equations describing the flow of a thin viscous film over a rough rotating disk are solved by either an analytical or numerical method. Depletion histories of the film are given for cases involving regular patterns of surface asperities. It is found that surface roughness markedly enhances the retention of a thin liquid film on a rotating disk. Moreover, different topographic structures of the surface roughness lead to different asymptotic limits of liquid retention.