涡流分级机环形区流场的激光多普勒测速研究

Study on flow fields in annular region of a turbo classifier by laser doppler velocimeter

采用激光多普勒测速计研究了涡流分级机环形区气流的切向速度分布。测量了蜗壳进口风速18 m/s时,从330 r/min到1800 r/min之间6个不同转笼转速条件下的环形区气流切向速度。结果表明:当转笼转速小于1 200 r/min时,转笼转速的变化对环形区气流平均切向速度的数值影响很小;转笼高速旋转,环形区气流切向速度数值大小与转速有关。用系数F表示转笼附近环形区气流切向速度波动程度与转笼转速之间的关系,当转笼低速旋转时F大,极小值点出现在转笼旋转速度与当地气流速度一致时,随着转速的增加,趋于平稳。

The tangential velocity distribution in the annular region of a turbo air classifier was investigated by laser doppler velocimeter （LDV）. Six tangential velocities in the annular region were measured at an inlet air velocity of 18 m/s when rotary speed of the rotor cage was from 330 r/min to 1 800 r/min. The results show that the effect of the rotary speed of the rotor cage on mean tangential velocity of air flow is little when the rotary speed of the rotor cage is less than 1 200 r/min. However, the tangential velocity has something to do with the rotary speed of the rotor cage in the case of high rotary speed. The relationship between fluctuating degree of tangential velocity in the vicinity of the rotor cage and rotary speed of the rotor cage is defined as F. F value is large in the ease of low rotary speed of the rotor cage. F value is minimum when the rotary speed of the rotor cage is equal to air velocity. F value becomes even with the increasing of the rotary speed of rotor cage.