The Mechanics of Particle-Filled Flows at High Solids Volume Fraction

Classical modeling predicts instability when a bed of powder is fluidized by gas. Older experiments by Rietema and colleagues, and more recent ones by Tsinontides and Jackson, present a compelling argument that, at least for Geldart Type-A powders, there exists an interval of stable fluidization. Moreover, these experiments indicate that constitutive models for the particle phase must account for plastic, solid-like, stresses, including tensile strength. We propose a simple one-dimensional model accounting for some of the observed behavior. We also present preliminary results from a numerical model for particle-fluid interaction.