激光成像技术在气泡生成行为研究中的应用

Formation Behavior of Gas Bubbles with Laser Image Visualization Technique

针对液相中单喷嘴的气泡生成过程,采用激光成像技术结合电荷耦合器件(Charge Coupling Device,CCD)摄像机照相方法研究了甘油水溶液中的气泡生成行为,结果表明该法能够获得清晰的二维气泡放大图像.考察了溶液浓度、气室体积、喷嘴直径和气体流量对气泡分离体积的影响,发现气泡分离体积分别随着溶液浓度和气室体积的增大而增大;在所研究的喷嘴直径(1,1.5和2mm)范围内,气泡分离体积随着喷嘴直径的增大而减小;气体流量对气泡分离体积的影响与喷嘴直径有关,当喷嘴直径为1和1.5mm时,气泡分离体积随着气体流量的升高而增大,但当喷嘴直径为2mm时,气泡分离体积随着气体流量的升高先减小后增大.

Laser image visualization technique, combined with photographing method by charge coupling device, has been employed to study single bubble formation at a submerged orifice in glycerol aqueous solution. The photographs show that magnified two-dimensional bubble images have been obtained clearly. The effects of solution concentration, chamber volume, orifice diameter and gas volumetric flowrate on bubble volume are investigated experimentally. It is found that bubble volume increases with solution concentration and chamber volume, respectively, and decreases with the increase of orifice diameter in the range of 1, 1.5 and 2 mm. The effect of gas volumetric flowrate on bubble volume is related to orifice diameter. Bubble volume increases with gas volumetric flowrate when using the orifices with the diameters of 1 and 1.5 mm, respectively, but employing the orifice with the diameter of 2 mm, bubble volume decreases first, and then increases.