Investigating Cylindrical Particle Fluidization Using X-Ray Particle Tracking Velocimetry (XPTV)

X-ray particle tracking velocimetry (XPTV) is used to determine the three dimensional particle motion and orientation characteristics of a cylindrical particle in a bubbling fluidized bed filled with a binary mixture of cylindrical particles and fluidizing material. Experiments are carried out in a 10.2 cm ID fluidized bed. Two types of cylindrical particles, Cylinder A (diameter d_i = 4.5 mm, length l = 7.1 mm) and Cylinder B (diameter d_i = 3.0 mm, length l = 16 mm), are used to evaluate the effect of particle shape. Glass beads with d_i = 300-500 μm are used at the fluidizing bed material. The cylindrical particles and bed material are carefully premixed using different mass ratios but a fixed static bed height of H = 10.2 cm. A single cylindrical particle is removed and tagged with a small metal rod as a tracer particle so that its motion and orientation can be simultaneously captured by two perpendicular X-ray imaging systems. XPTV is used to provide a detailed three dimensional trajectory map of the tracer particle. The effect of various operating parameters on the cylindrical particle position, velocity, and orientation will be discussed.