Computation of the drag force on a sphere close to a wall: The roughness issue

Abstract

We consider the effect of surface roughness on solid-solid contact in a Stokes flow. Various models for the roughness are considered, and a unified methodology is given to derive the corresponding asymptotics of the drag force in the close-contact limit. In this way, we recover and clarify the various expressions that can be found in previous studies. © EDP Sciences, SMAI, 2012.