喷射式环流反应器内流速分布的实验研究

主要研究了喷嘴位置和喷嘴出口速度对底部是圆锥台的喷射环流反应器(JLR)的影响,从而确定最优出口速度和喷嘴位置。对JLR内部流速进行测量,绘出JLR内的速度分布图,并从速度场和内外循环比2个方面进行分析,从而确定最优参数。结果表明:在实验室范围内,当喷嘴出口速度为2.1 m/s,喷嘴位置为40 mm时较优。导流筒内速度呈抛物线分布;喷嘴出口速度增加,环隙速度对应增大,内外循环比也增加;随着喷嘴位置逐渐靠近导流筒,内外循环比先增加,再减小。

Experimental research on velocity distribution within jet loop reactor

The effect of outlet velocity and location of nozzle on jet loop reactor(JLR) whose bottom is designed for truncated right angle cone was studied,and the optimal outlet velocity and location of nozzle were determined sequentially.The velocity was measured and the speed distribution within JLR was drawn.The velocity field and the flow ratio of internal reflux flow to external reflux were analyzed,and the optimal parameters were determined.The result indicates that the optimal outlet velocity is 2.1 m/s and the location of nozzle is 40 mm.The liquid velocity presents parabolic in radial distribution with the highest velocity at the central axis of the draft tube.With the increasing of outlet velocity,the liquid velocity in downcomer increases,and the volume flow ratio of internal reflux to external reflux increases;when the jet nozzle location raises from a lower position to a higher position,the volume flow ratio of internal reflux to external reflux increases first and then decreases,and the liquid velocity in downcomer is subject to the same rule.