基于CFD-PBM耦合方法的栅条絮凝池内颗粒聚并行为模拟

柴彤山; 伏雨; 程怀玉; 龙新平

doi:10.13205/j.hjgc.202304006

基于CFD-PBM耦合方法的栅条絮凝池内颗粒聚并行为模拟

doi: 10.13205/j.hjgc.202304006

柴彤山^1,2,
伏雨^1,2,
程怀玉^1,2,
龙新平^1,2, ,

1. 水射流理论与新技术湖北省重点实验室, 武汉 430072;
2. 武汉大学动力与机械学院, 武汉 430072

基金项目:

国家自然科学基金(12072243)

详细信息

作者简介:
柴彤山(1998-),男,硕士研究生,主要从事流动模拟研究。chai_tongshan@whu.edu.cn

通讯作者:
龙新平(1967-),教授,博士生导师,主要从事流动模拟和流体喷射技术研究。xplong@whu.edu.cn

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出版历程
- 收稿日期: 2022-03-24
- 网络出版日期: 2023-05-26
- 刊出日期: 2023-04-01

NUMERICAL SIMULATION OF PARTICLE AGGREGATION IN GRID FLOCCULATION TANK BASED ON CFD-PBM

CHAI Tongshan^1,2,
FU Yu^1,2,
CHENG Huaiyu^1,2,
LONG Xinping^{1,2
, ,}

1. Key Laboratory of Hubei Province for Waterjet Theory and New Technology, Wuhan 430072, China;
2. School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, China

摘要

摘要: 为探究絮凝池内部颗粒聚并行为的影响因素,采用群体平衡模型(PBM)模拟颗粒聚并行为,通过CFD-PBM耦合方法,研究了絮凝颗粒初始平均粒径和絮凝颗粒体积分数对栅条絮凝池内部颗粒聚并行为的影响,提出了颗粒平均粒径增长率指标来表征CFD-PBM耦合方法下絮凝池内部絮凝效果。结果表明:1)当进口颗粒体积分数为0.1时,随着絮凝颗粒初始平均粒径由10 μm增长到76 μm,出口处粒径由117.54 μm增长到154.82 μm,但颗粒平均粒径增长率由1075.4%迅速降低至103.7%;2)在进口颗粒初始粒径为40 μm时,随着颗粒体积分数由0.05增长至0.2,出口位置颗粒粒径由127.16 μm增加至155.74 μm,而平均粒径增长率也随之由208.7%增加至289.4%;3)从整体上来看,当颗粒体积分数从0.05增加到0.1时,平均粒径增长率的变化最快,絮凝效果的提升最为显著。研究结果对于栅条絮凝池的结构设计指导和絮凝效果评价具有重要意义。
- 水力絮凝 /
- 颗粒聚并 /
- 群体平衡模型 /
- 数值模拟
Abstract: In order to explore the influencing factors of particle aggregation behavior in the flocculation tank, the population balance model (PBM) was used to simulate the particle aggregation behavior in this paper. By means of CFD-PBM coupling method, the effects of initial average particle size and volume fraction of flocculated particles on particle aggregation behavior in a grid flocculation tank were studied. An index of average particle size growth rate was proposed to characterize the flocculation effect inside the flocculation tank under the CFD-PBM coupling method. The results showed that: 1) when the inlet particle volume fraction was 0.1, as the initial average particle size of flocculated particles increased from 10 μm to 76 μm, the particle size at the outlet increased from 117.54 μm to 154.82 μm, but the average particle size growth rate decreased from 1075.4% to 103.7%; 2) when the initial particle size of the inlet particles was 40 μm, as the particle volume fraction increased from 0.05 to 0.2, the particle size at the outlet position increased from 127.16 μm to 155.74 μm, and the average particle size growth rate also increased from 208.7% to 289.4%; 3) overall, within the particle volume fraction range of 0.05 to 0.1, the average particle size growth rate was the highest, and the flocculation effect improved most significantly.
- hydraulic flocculation /
- particle aggregation /
- population balance model /
- numerical simulation

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