With the principles of similarity and dimensional analysis, the cast iron pulverized coal was enlarged from 0.5 mm to 2 mm. The virtual experiment was carried out to calibrate the basic contact parameters of scaled particles. The simulation of particle movement in vertical screw conveyor with discrete element model was carried out to verify the exactness of the scaling method. The results showed that when the screw rotation speed is 500, 550, 600, 650 r/min, particle axial velocity and peripheral speed is increased. The maximum axial velocity is in the upper part and on the verge of blade, respectively 0.486, 0.535, 0.596, 0.657 m/s. The axial velocity decreases obviously in area more than spiral radius. Compared with simulation and experiment, the mass flow rate in the device outlet and particle axial velocity is true on the whole and meets the principles of similarity under the reasonable approximations.
Jianli REN Longhai ZHOU Long HAN Jiani ZHOU Mi YAN
. Discrete Simulation of Vertical Screw Conveyor Based on Particle Scaling Theory[J]. The Chinese Journal of Process Engineering, 2017
, 17(5)
: 936
-943
.
DOI: 10.12034/j.issn.1009-606X.217109
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