Abstract: The mixing effect in two horizontal opposed impinging stream mixer under turbulent flow condition was studied by using plane laser induced fluorescence (PLIF) technique, the influence of Reynolds number, the nozzle separation, the nozzle diameter and the inlet velocity ratio. The results showed that when the distance between two nozzles L increased from d’ to 3d’ (d’ was the average inner diameter between two nozzles), the mixing time decreased, but when L increased from 3d’ to 5d’, the mixing time increased, when L was 3d’, the mixing time was the smallest. When the Reynolds numbers was equal to 17544 at both ends of the inlet, the mixing time gradually decreases as the diameter of the nozzle increased from 6 mm to 14 mm, but the trend gradually slowed down. When the ratio of the inlet velocity of the two nozzles increased from 0.71 to 1.67, the mixing time decreased and then increased, when the velocity ratio was 1, the mixing time was the smallest. With the Reynolds number increasing from 7519 to 40936, the mixing time decreased. The mixing effect was best when L was 3d’ under symmetrical impact, the increase of nozzle diameter and Reynolds number can enhance the mixing effect significantly.

Key words: impinging stream, mixing effect, PLIF, turbulent

摘要： 采用平面激光诱导荧光技术(PLIF)对浸没状态下水平对置双向撞击流混合器在湍流时的混合情况进行了研究，考察了进口处雷诺数(Re)、喷嘴间距、喷嘴内径、进口速度比对混合效果的影响. 结果表明，对称撞击下，喷嘴间距L从d’增加至3d’时(d’为两喷嘴内径平均值)，混合时间减小；L由3d’增加至5d’时，混合时间增加，L＝3d’时混合时间最小. 两端进口处Re=17544时，喷嘴内径由6 mm增至14 mm，混合时间减小且减小趋势逐渐放缓；两喷嘴进口速度比由0.71增至1.67时，混合时间先减小后增加，速度比为1时，混合时间最小；雷诺数Re由7519增至40936时，混合时间减小. 对称撞击下，L=3d’时混合效果最好，增加喷嘴内径及雷诺数可显著提高混合效果.

关键词: 撞击流, 混合效果, 平面激光诱导荧光技术, 湍流