竖流式二沉池的数值模拟与分析  

A Numerical Simulation Analysis of Vertical Secondary Settling Tanks

作　　者：刘凤凯[1] 张永丽[1] 李方才 

机构地区：[1]四川大学建筑与环境学院,成都610065 [2]彭州市生源水务有限公司,四川彭州611930

出　　处：《中国农村水利水电》2014年第2期75-78,共4页China Rural Water and Hydropower

基　　金：教育部创新团队项目(ITR1027)

摘　　要：为了了解竖流式二沉池最佳工作效果,利用RNGk-ε紊流模型和Mixture模型,对其进行二维瞬态数值模拟,得到了不同运行时刻沉淀池内部的流场和污泥质量浓度分布等情况。研究结果表明:竖流式二沉池运行过程中流场变化较大,其间产生的回流区会导致不同程度的短流现象;运行至2h后沉淀池内流速分布逐渐均匀,平均沉淀时间接近设计值;随着池内污泥质量浓度的升高,有效沉淀高度会减小,应合理控制排泥间隔时间;研究还发现沉淀池内存在着明显的泥水界面和压缩界面。To investigate the optimum working condition of vertical secondary settling tanks, the RNGκ-ε turbulence model and mixture model are used for 2d unsteady simulation of the flow field and sludge concentration in settling tanks. The simulation results show that the flow field changes a lot and the recirculation zone results in short-streams. After it works for 2 hours, the velocity distribution in the tank becomes uniform and the average settling time approaches the design value. An effective sediment height reduces with the increase in sludge concentration in the tank, so it is reasonable to control the sludge discharge interval. And there are two visible interfaces of sludge-water interface and sludge thickening interface in the vertical secondary settling tank.

关 键 词：竖流式二次沉淀池 数值模拟 异重流 瞬态 

分 类 号：TU991[建筑科学—市政工程]