Reply to comment on: On a sphere performing linear and torsional oscillations in a viscous fluid

Abstract

Equation [2] in the paper of Karahalios and Sfetsos (1) shows that there is a permanent radial flow at infinity, due partly to torsional oscillation, whereas it should be confined to a finite distance from the sphere. Consequently, a second (outer) boundary layer extending beyond the Stokes (inner) boundary layer is assumed to exist. The inertia terms in this outer layer are not negligible, and the solution is taken in the form