Summary: | 碩士 === 大同大學 === 化學工程研究所 === 90 === Experimental study was conducted on residence time distribution (RTD) obtained for gas flow at the spouted and jet spouted regimes in the conical-cylindrical bed. Experimental parameters investigated included gas velocity, particle sizes and stagnated bed height. All the experiments were carried out in an 188mm I.D. transparent acrylic bed with an inclined angle of 40o, and the range of particle sizes from 0.645 to 2.171mm. The effects of gas velocity, particle sizes and stagnated bed height on the axial dispersion coefficient were determined from the axial dispersion model. It is found that axial dispersion coefficient increases with increasing the gas velocity, stagnated bed height and decreasing the particle sizes in the spouted and jet spouted beds. The empirical correlations for axial dispersion coefficient on the spouted and jet spouted beds are proposed to fit the experimental data. It indicates that estimated values of dimensionless dispersion group, Da are in agreement with experimental data within 20%.
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