| In order to achieve gas-solid flow control in guide vane cyclone tube, diversion tube and dust discharge cone were used in the resistance characteristics and solid particle separation experiment. The flow control structure's effect on the separation performance of cyclone tube was got and confirmed different type of cyclone by a combination of flow control structures. The results showed that cyclone tube's pressure drop reduced when diversion tube had slots in sidewall, the separation efficiency of 1-20μm particle increased an average of 3.0% and it was maximum while the slot area ratio was 3.0, the separation efficiency of 2μm particle increased 6.7% compared to reference structure when diversion tube had lower slots. Dust discharge cone with different height-diameter ratio needed different width of slots to reduce pressure drop and increase separation efficiency.The control effect on main flow and secondary flow in cyclone tube was analyzed by flow field measurement and numerical calculation. The equilibrium orbit model in diversion tube's slot was built on the basis of the flow field data. The results showed that tangential velocity and axial velocity in cyclone tube decreased as diversion tube's slotted area ratio increased. Downstream flow region expanded by 2.5 times with slots in different position of diversion tube. The short circuit flow in exhaust tube was greatly weakened through diversion flow. The suitable ratio between diversion flow and downstream flow was the key to flow control in exhaust tube. There was a large velocity gradient because of the jet velocity from slots was faster than the velocity of air flow within the dust hopper when dust discharge cone had 20mm slots. The velocity difference between jet flow from slots and air flow within the dust hopper was the key to flow control in dust discharge cone.The gas-solid-phase flow filed in the cyclone separator was numerical studied by using the commercial software FLUENT. It is found that the cyclone separator with slotted vortex finder has higher collection efficiency, and a lower pressure-drop. Three-dimensional simulation results of gas flow in the SVF separator indicate that the slotted vortex finder acts as a blade louver separator. The results also indicate that the slotted vortex finder could reduce the short circuit flow rate at the bottom of the vortex finder. On the basis of the gas flow field, solid particle trajectories were simulated by using the two-way coupling lagrangian scheme. The results show that most fine particles escape out of the separator though the upper slots. The results show that the flow rate of gas running into exhaust pipe through the vortex finder slots increases with the increases of the slot area, and the flow rate retains constant when the slot area ratio is more than 2.9; the short circuit flow rate is reduced by the slotted vortex finder and less than 5% of the inlet flow when the slot area ratio is more than 1.94. The number of escaped particles though slots increase as the slot area increases, and the number of the escaped particles though vortex finder bottom decrease as the slot area increases. Besides, the effects of the vortex finder structural parameters on the gas-solid- phase flow were studied to provide references for the design and operation of cyclone separator, including the width of the slot in the vortex finder and the angle of the slot. The above results have a certain reference value for the research on the separation mechanism of cyclone separator.Based on the study of the gas and solid two phase flow in the cyclone tube, a calculation model for cyclone perfermence was deduced with use of multiple linear regression method. Compared with the industry data, this model showed a good agreement and could be used for industry design.
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