3-DIMENSIONAL INTRINSIC CONVECTION IN DILUTE AND DENSE DISPERSIONS OFSETTLING SPHERES

The three-dimensional intrinsic convection in a monodisperse dispersio n of spheres settling in a vertical container of arbitrary cross secti on is calculated using the simple model of point forces with excluded volume near the walls, proposed by Bruneau ct al. [Phys. Fluids 8, 223 6 (1996)]. An exact solution of the model equations for a container wi th rectangular cross-section shows that corners have no significant in fluence on the convection. A dense suspension is modeled by assuming a n equilibrium particle distribution in the near wall region. It is pre dicted that as a result of near wall ordering, the intrinsic convectio n decreases with increasing particle volume fraction. (C) 1998 America n Institute of Physics.