曝气池内气泡羽流附壁效应的试验研究  

Coanda effect of bubble plume in aeration tanks

作　　者：肖柏青[1,2] 张法星[2] 刘春艳[2] 李然[2] 

机构地区：[1]安徽理工大学地球与环境学院,安徽淮南232001 [2]四川大学水力学与山区河流开发保护国家重点实验室,成都610065

出　　处：《水力发电学报》2012年第4期104-107,112,共5页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金资助项目(50978173)

摘　　要：曝气池中气泡羽流在边墙附近的流动特征对污水处理效果的影响至关重要。为了探明曝气池中气泡羽流在附壁效应(Coanda效应)下的偏移规律,在配置有橡胶膜式微孔曝气盘的大型蓄水池中进行了曝气池模型试验。试验中利用针式掺气浓度仪测量得到不同工况下气泡羽流的气含率分布,进而分析得到气泡羽流的倾斜程度。试验结果表明,气泡羽流的倾斜程度主要受曝气盘距边壁的距离以及通气量影响,而与水深的相关关系并不显著。采用量纲分析方法,建立了曝气盘到边壁的距离和通气量对气泡羽流倾斜影响的数学模型。Flow behavior of bubble plume rising near the side wall of aeration tank is important to design of sewage treatment. To study the Coanda effect of bubble plume and its inclination near the wall, a model test in a large aeration tank was carried out. Fine gas bubbles were generated by a EDPM membrane diffuser, the distribution of plume gas holdup were measured with a electro-resistivity phase-detection gauge, and by using these distributions the plume inclination under different conditions were obtained. The measurements show that the air flow rate and the distance of bubble-generating diffuser to the wall are major factors determining the near-wall plume inclination, while the water depth in the tank plays little role. A mathematical model for estimation of the effects of these factors was developed using dimensional analysis method.

关 键 词：水力学 附壁效应 气泡羽流 曝气池 

分 类 号：TV137[水利工程—水力学及河流动力学]