Summary: | 碩士 === 建國科技大學 === 機械工程系暨製造科技研究所 === 100 === This study established a rotating gas-solid fluidized bed equipment to investigate the flow behaviors and drying efficiency of rotating granular powders. A high speed camera system is used to observe the complex flow behaviors due to the centrifugal force, the fluid drag force and the interaction forces between particles. The glass beads with different sizes are used as the granules in the experiment. The experimental parameters include the particle size, the rotation speed and the superficial gas velocity. This study is divided into two stages: firstly, the flow behaviors of rotating fluidized bed with mono-disperse and binary mixtures are performed to examine the relationship between pressure drop and critical fluidization velocity. The experimental results are compared with the theoretical value of Ergun equation. Secondly, the drying efficiency of wet particles is performed with different rotating conditions. The experimental results show that the pressure drop and critical fluidization velocity increased with the particle size and the rotating speed for both mono-disperse and binary mixtures. In the cases of binary mixtures, the pressure drop and critical fluidization velocity decreased with the concentration of small particles. The outlet temperature drop period decreased with the increase of rotating speed for both mono-disperse and binary mixtures. The outlet temperature drop period decreased with the decrease of concentration of small particles for the cases of binary mixtures.
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