本文采用流动显示的方法对平板混合层中上下层流体速度比对固体颗粒在混合层中沉降的影响进行了研究。实验中分别采用粒径小于40 μm,粒径98~104μm,粒径154~160μm的玻璃微珠以及环氧树脂作为固相颗粒,对这些颗粒在速度比分别为1:1.2、1:2和1:2.8的液相混合层中的运动进行了显示。结果表明混合层中大涡结构对固体颗粒的沉降具有迟滞作用,其作用程度取决于混合层中上下层流体速度比。速度比越大,颗粒的沉降越慢
The effects of velocity ratio of free streams on the particlesedimentation in liquid-solid two phase plane mixing layer are studied by flowvisualization method. The glass spheres with three diameter ranges (less than40 μm, 98~104 μm and 154~160 μm) and epoxy particlesare used as solid phase respectively. The motion ofthese solid phase particles are visualized in mixing layers withvelocity ratio 1:1.2,1:2 and 1:2.8, respectively. The visualizationshow that the large vortex structures counteract the sedimentation ofparticles in mixing layer. The intensity of counteraction is determinedby the velocity ratio between two free streams of mixing layer. The morethe velocity ratio, the slower the particle sedimentation
参考文献
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