Conference Dates

May 16-21, 2010


The ability of computational fluid dynamics to predict the expansion and segregation of a binary solids mixture in a liquid-solid fluidized bed is investigated. Unsteady laminar flow is simulated by a modified two-dimensional Eulerian-Eulerian model in Fluent 6.3. The predictions are compared with experimental results for binary particles in the same narrow (1.00-1.18 mm) size range, but with different densities, 1600 and 1900 kg/m3, fluidized by water (1). The voidages and heights of two layers which form, each dominated by one particle species, were found to be sensitive to small changes in particle properties (diameter, density, sphericity), as well as temperature (because of its effect on the water viscosity). As a result, agreement between simulations and experimental results depends on several incompletely characterized factors. Temperature via the water viscosity greatly influences heights and volume fractions of the two layers. Allowing for non-spherical particle shapes is also crucial in reconciling predictions and experimental data.