基于PLIF的浸没撞击流反应器的混合特性

利用平面激光诱导荧光技术对水平两喷嘴液-液撞击流反应器内的浓度场进行定性和定量分析，用离析度(IOS)评价时均混合效果，得到不同操作条件下IOS值沿径向射流方向的变化规律，并与三喷嘴的情况进行对比. 结果表明，喷嘴间距L、喷嘴直径D和进口流量Q对反应器混合效果有重要影响，在水平两向撞击流中，当喷嘴直径和流量一定时，随喷嘴间距增大，IOS下降速度加快，最佳间距为L/D=3；当喷嘴间距和流量一定时，随喷嘴直径增大，IOS下降更快，下降到IOS=0.05所需距离不断减小，最佳喷嘴直径D=12 mm；当喷嘴直径和喷嘴间距一定时，随流量增加，IOS下降速度先增加后减小，最佳流量Q=500′10-3 m3/h. 三喷嘴撞击流与两喷嘴变化趋势一致.

Mixing Characteristics in an Immersed Impinging Stream Mixer with PLIF Technique

The concentration field in a horizontal double-nozzle liquid-liquid impinging stream mixer was analyzed qualitatively and quantitatively with planar laser induced fluorescence technique. The time average mixing efficiency was evaluated withg intensity of segregation (IOS), its varation along the radial direction of jet flow was examined under different operation conditions, and compared with that in the three-nozzle impinging mixer. The results show that the distance between nozzles (L), diameter of nozzle (D) and lquid flow rate (Q) have important effects on the mixing efficiency. In the horizontal double-nozzle impinging mixer, the declining speed of IOS increases with the increase of L under the same D and Q, the optimal L is 3D. The declining speed of IOS increases with the increase of D, reaching 0.05, the necessary distance continuosly decreases, the optimal D is 12 mm. Under the same D and L, the declining speed of IOS increases first and then decreases with the increase of Q, the optimal Q is 500′10-3 m3/h. The three-nozzle impinging stream and horizontal double-nozzle one have the similar changing trend.