Circulation of Geldart D type particles: Part I – High solids fluxes. Measurements and computation under solids slugging conditions

Solids slugging phenomena were studied in a symmetric IIT riser using gamma ray densitometers. No core-annular regime was observed at high solids fluxes. Computations using the kinetic theory based IIT CFD code confirmed the elimination of the undesirable core-annular regime.The computer code was also used to calculate dispersion coefficients. The computed radially averaged total granular temperatures, axial and radial solids dispersion coefficients and axial gas dispersion coefficients agreed well with the literature. The −5/3 Kolmogorov energy spectrum law was followed at high frequencies. The dimensionless form of the spectral distribution showed good agreement with the Hinze correlation for single phase flow turbulence. The IIT CFD code computed high slip and anisotropy in the fluidized bed system.