低气流量时水下微米级针管气泡生成实验研究

Experimental Study of Bubble Formation From a Submerged Micron Nozzle

目前国内外的水下气泡生成现象研究主要集中在毫米级尺寸的孔洞和针管,微米级的研究相比很少。本文通过自行搭建的实验平台,利用高速摄影的方法,对0.110 mm内径的针管产生水下气泡的行为特点进行了系统的可视化实验并利用Matlab编程对图像进行处理分析,定量分析气泡的形态参数。文中对单气泡生长过程的阶段性、周期性和部分参数变化作了详细讨论,实验中还发现了更高气流量下的多气泡合并现象,并得到气泡脱离体积随气体流量的变化特点。

At present the researches of bubble formation process from orifices and nozzles mainly focus on the millimeter dimension level, while the studies about the micron level are much less. In this paper, with high speed camera, visualization experiments and systematic analysis were carried out to investigate the bubble dynamic behaviors at the submerged O.110 mm diameter nozzle. Matlab program was made to analysis bubble character parameters. The different stages, periodicity and some other parameters of single bubble during its formation were discussed in detail. It was found that the coalescence bubbling phenomenon appeared when the gas flow rate got higher and the variation of the bubble detachment volume with the gas flow rate was obtained.