The influence of the superficial gas velocity on the residence time distributions (RTDs) of large spherical objects of different densities in the dense phase of a fluidized bed was studied using electrical capacitance tomography (ECT) tracing technique. The regularity and randomness of the motion of a large object were decided by a probabilistic statistical analysis to investigate the mechanical characteristics of an object in a bed. The results show that decreasing the fluidization velocity first slowly reduces the residence time. When the gas velocity is lower than a critical value, the residence time sharply increases until the object does not reach the low side of the air distributor. Heavier objects have higher critical gas velocities. The RTD curves are very broad due to the stochastic pressure and velocity pulsations in the fluidization bed.
蔡容容,张衍国,蒙晨玮,李清海,蒙爱红. 重质大颗粒在非均匀布风流化床内停留时间[J]. 清华大学学报（自然科学版）, 2014, 54(6): 775-780.
Rongrong CAI,Yanguo ZHANG,Chenwei MENG,Qinghai LI,Aihong MENG. Residence time of a large heavy object in a fluidized bed with an uneven air distribution. Journal of Tsinghua University(Science and Technology), 2014, 54(6): 775-780.
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2014, Vol. 54 
),蒙晨玮,李清海,蒙爱红
