Creeping fluid flow relative to an assemblage of composite spheres

Abstract

Incompressible creeping flow of a Neewtonian fluid relative to an assemblage of composite particles has been examined analytically. An individual particle iomposed of a solid sphere of radius a embeddd in a porous spherical shell of thickness (b-a). The relevant governing equations have been combined with the well knoown free surface cell model of Happel to incorporate interparticle interactions of o the analysis. Detailed streamline patterns are presented embracing wide ranges of combinations of the size, thicknesss of porous region, permeability of porous medium, and concentration tf th suspension or assemblage. An analytical expression for the drag force experienced by the assemblage is also given.