Published online by Cambridge University Press: 21 April 2006
A rotating tank is filled from the outside with a mixture of particles and fluid. Under certain attainable conditions on the times for filling, separation, and spin-up, theory implies that the filling process acts like a centripetal separator in which heavy particles are actually concentrated at the inward-moving front. Centrifugal settling in the interior is counteracted by mass transport in the rotating boundary layers to produce this unusual volume-fraction distribution.