Unsteady-state transfer between a sphere and a surrounding stationary medium with application to arrays of spheres (Q1058420)

A series solution is presented for transfer between a sphere and a surrounding stationary medium enclosed in a concentric insulating spere. It is shown that after a period, short compared to the time necessary to transfer a small proportion of the maximum quantity transferable, the first term of the series dominates. The transfer process then proceeds with a constant Nusselt or Sherwood number determined only by the ratio of the radii of the spheres.