ABSTRACT
In both the models, the fluid was taken to be air, with a density of 1.2 kg m−3 and a viscosity of 1.8 × 10−5Pa s.
3 CONVECTION
Convective motion within a vibrated system of particles has been investigated experimentally and by using numerical simulations (Knight et al. 1996; Taguchi 1992). Most studies have used large particles for which the influence of air can be neglected. The convective motion results from both granular collisions with other particles and interactions with container walls. Here we show that, when the particulates are small enough, fluid plays a major role in the resulting convective motion.
