AN EXPERIMENTAL-STUDY ON THE EFFECT OF PARTICLE-SHAPE ON FLUIDIZATION BEHAVIOR

Few correlations exist to describe the effect of particle shape on the relationship between superficial velocity and void fraction in homogeneous fluid beds. Limestone, quartz, bottom ash and pea gravel particles were fluidized with water and a data bank of void fractions and fluidizing velocities was compiled. Each particle type was image analyzed to yield average shape descriptors, namely aspect ratio, fractal dimension, polygonal harmonic persistences and delta (Piper's) angles. Regression showed that the slope of a log (superficial velocity) versus log (void fraction) plot can be fitted using a function of a shape descriptor, with the persistence of the third harmonic being the descriptor yielding the best fit.