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| Numerical Simulation of Dense Gas-solid Two Phase Flow in a Steady-state Fluidized Bed |
| ZHANG Jian-hui, WANG Li-ya, LUO Bi-hui, ZHENG Yan-zhen |
| School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou 310018, China |
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Abstract To investigate the influence of the furnace structure and inlet gas velocity on gas-solid two-phase flow states in the deposition furnace, FLUENT software was used to simulate dense gas-solid two-phase flow in a fluidized bed. The results show that the dispersed fluidized bed formed in the deposition furnace with a cone angle of 60° has the structure of "ring-nucleus" and longer gas retention time compared with the flat-bottom structure deposition furnace, which is beneficial to the preparation of the pyrolytic carbon coating materials with a uniform structure and excellent quality. Inlet gas velocity should be moderate, the slow inlet gas velocity leads to the chaos of the particle velocity distribution, which cannot form the ring-core flow structure. High inlet gas velocity leads to the back mixing of particles in the deposition furnace. In addition, as the inlet gas velocity increases, both the gas phase and the average particle velocity in the central area of the deposition furnace gradually increase, and the effect of the gas phase velocity is more obvious.
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Received: 12 January 2021
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Corresponding Authors:
ZHANG Jian-hui. E-mail: zhangjh@hdu.edu.cn
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