Quantification of Riser Hydrodynamics

High speed video analysis was done for riser hydrodynamics of Geldart Group A and B material in a 12-inch (0.3-m) diameter by 60-ft (18-m) tall riser, 12-inch (0.3-m) diameter by 49-ft (15-m) tall riser, and 8-inch (0.2-m) diameter by 72-feet (22-m) tall riser.  Analysis of video results clearly showed the core annulus profile with both upflow and down flow at the wall, the cluster formation and stability resulting from transient gas jets and particle rotational velocities.  Detailed particle tracking analysis (HSPIV) further revealed shear near the wall plus the radial granular temperature profile.