Upflow of solid/gas suspensions: The role of particle particle and particle-gas interactions

We consider a two-continua model (Ocone et al, 1993) applied to riser now, and we explore how the solution depends on some parameters (particle-particle and the particle-wall coefficient of restitution), and how the results in the various cases compare with experimental data (Bodelin et a!, 1993). Results are reported which show that the model can predict the correct dependence of the pressure gradient on particle mass flux, and the occurrence of ''lean'' and ''dense'' regimes.