Experiment on centripetal motion of air bubble in turbulence generator
YE Daoxing1,2, LI Hong3, LAI Xide2
1.Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, Sichuan 610039, China; 2.School of Energy and Environment, Xihua University, Chengdu, Sichuan 610039, China; 3.National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China
Abstract：The motion characteristic of air bubble was investigated analytically and experimentally. The forces on an air bubble were analyzed and its velocity and trajectory equations were derived, the unsteady motion characteristics of air bubble were studied. An experimental set-up was established to visualize the two-phase flow field of air-water. The air bubble motion images in a turbulence generator were taken by making use of high speed photography technology. The unsteady motion trajectory of the air bubbles with diameters 0.8, 1.5, 1.9 mm were obtained at 80, 130 and 200 r/min generator rotational speeds, respectively, by using image processing method. It was found that the radial position of an air bubble is not only related to the rotational angle of the turbulence generator with an exponential function, but decreased rapidly with increasing air bubble diameter and generator rotational speed. The results revealed that an increased generator rotational speed can accelerate air bubble to move centripetally and the air bubbles with larger diameter can arrive at the rotating hub by taking the lead. The experiment observations were in agreement with analytical results basically, and the key factors influencing centripetal motion of air bubble were identified, providing a base for further study.
叶道星,, 李红, 赖喜德. 湍流发生器中气泡水平向心运动试验[J]. 排灌机械工程学报, 2017, 35(11): 947-953.
YE Daoxing,, LI Hong, LAI Xide. Experiment on centripetal motion of air bubble in turbulence generator. Journal of Drainage and Irrigation Machinery Engin, 2017, 35(11): 947-953.
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