INTRINSIC CONVECTION IN A SETTLING SUSPENSION

The intrinsic convection in a settling suspension is shown to have its origins in the buoyancy of the particle-depleted layer next to the si de walls. The convection is calculated using a simple model in which t he particles are represented by an excluded volume and by point forces at their centres. A boundary layer approximation is developed for ves sels which are much wider than the particle diameter. It is shown that the direction of the convection depends critically on assumptions abo ut the formation of the particle-depleted layer during the placement o f the suspension into the vessel. (C) 1996 American Institute of Physi cs.