Mixing and regime transition analysis of liquid-solid conical fluidized bed through RPT technique

Abstract

The current work focuses on the hydrodynamic study of liquid-solid mono and binary conical fluidized bed using the radioactive particle tracking technique. Two different sizes 0.6 and 1 mm diameter glass beads were used for the experiment. Two different bed compositions, mono dispersed (100 wt% of each solid) and 50 wt% mixture of the solids, were studied. A rich data base, including instantaneous velocities, mean and RMS velocities, granular temperature, etc., were calculated by suitable post-processing. Further, Hurst exponent, autocorrelation function, segregation index, Kolmogorov entropy, and correlation dimension were calculated using time series data to understand the mixing and chaotic nature of the fluidized bed for each set of data. Good degree of mixing was observed even at a low velocity of 0.07 m/s. Kolmogorov entropy and correlation dimension indicate regime change at liquid inlet velocity of 0.1 m/s for both mono and 50 wt% binary bed.