Effect of Particle Shape on Fluidized Bed Hydrodynamics Using X-ray Tomography and Pressure Measurement
Zhang, Q., Wu, B., Li, Y., Bellehumeur, C. and Kantzas, A.
5th World Congress on Industrial Process Tomography, Bergen, Norway, September 3-6, 2007.
In gas-solids fluidised beds, particles with different shapes will affect bed packing properties, granular flow, and hydrodynamics. In this paper, an X-ray computer assisted tomography (CAT) scanner and pressure transducers were utilized to investigate the effect of particle shape on the behaviour of gas- solid flow in a 20-cm diameter column under ambient conditions. Glass beads and sand were used as solid phase, and air was used as gas phase. Two 2-D descriptors, roundness and aspect ratios were used to characterize the particle shape, which was measured by optical microscopy. The time- averaged bed voidage, voidage distribution and bed expansion were analysed at different superficial gas velocities and bed heights based on the reconstructed images. The estimated bubble diameter was obtained using pressure fluctuation analysis.