辐流式沉淀池进口挡板影响的液固两相流数值模拟  

Numerical simulation of a feed flow baffle on the flow of a radial sedimentation tank by using a liquid-solid two-phase model

作　　者：魏文礼[1] 张泽伟[1] 白朝伟[1] 刘玉玲[1] 

机构地区：[1]西安理工大学陕西省西北旱区生态水利工程重点实验室,西安710048

出　　处：《应用力学学报》2016年第1期93-98,183,共6页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(51578452;51178391);陕西省科学研究计划项目(2014K15-03-05);中央财政支持地方高校发展专项资金特色重点学科项目(106-00X101)

摘　　要：采用RNG k-ε两方程紊流模型以及简化的多相流Mixture(混合)模型对进口处不同长度的两种垂直挡板的辐流式二次沉淀池内的液固两相流进行了三维数值模拟,得到了沉淀池内的流场分布、污泥浓度分布、速度分布。速度与压力耦合方程组求解时使用半隐式SIMPLE(SemiImplicit Method for Pressure-Linked Equations)算法。通过对这两种不同挡板池内的水流流场、浓度场、速度场的模拟分析,结果发现:长挡板形式下的辐流式沉淀池内水流流场更有利于污泥快速沉淀,即有利于固液分离,使得出口水质明显提升;同时也说明合理改变沉淀池的结构体形与尺寸,可以改善沉淀池内的流场流态,提高沉淀效果和运行效率。The RNG k- ε turbulent model with simplified mixture multiphase model is used to simulate 3D solid-liquid two-phase flow in a secondary sedimentation tank. In the simulation process, the flow field, sludge concentration distributions and velocity distributions of the sedimentation tanks are obtained. The coupling velocity and pressure equations are solved with the SIMPLE(Semi-Implicit Method for Pressure-Linked Equations)algorithm. The two radial sedimentation tank models with two different forms of vertical baffles at the inlet are used for the simulation. The analysis of the simulated flow field, sludge concentration distributions and velocity distributions of the two different models shows that the flow field distribution of the longer baffle is more conducive to make sludge rapidly settle down, and the resultant separation of solid and liquid significantly improves water quality. The research result also shows that the reasonable structure shape and size of a sedimentation tank can improve its flow field and sludge concentration distributions, and also increases sedimentation effects and improves operating efficiency of sedimentation tanks.

关 键 词：辐流式沉淀池 数值模拟 流场 浓度场 

分 类 号：TV131.4[水利工程—水力学及河流动力学]