Stochastic simulation of the flow of a thin liquid film over a rough rotating disk

This article addresses the depletion of thin liquid films due to centrifugation. A stochastic model of surface roughness is used, and the equation describing the flow of a thin viscous film over a rough rotating disk is solved by Monte Carlo techniques. Depletion histories of the thin film are given for several cases involving random surface asperities. It is found that surface roughness markedly enhances the retention of a thin liquid film on a rotating disk. The thinner the liquid layer, the more dominant is the effect of surface roughness. Moreover, different degrees of randomness of the surface asperities lead to different asymptotic limits of liquid retention.