NUMERICAL SIMULATION AND ANALYSIS OF FLOW FIELD AND PARTICLE MOTION IN GRID FLOCCULATION TANK

FU Yu; LONG Yun; XIAO Bo; CHENG Huai-yu; LONG Xin-ping

doi:10.13205/j.hjgc.202104005

Volume 39 Issue 4

Jul. 2021

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FU Yu, LONG Yun, XIAO Bo, CHENG Huai-yu, LONG Xin-ping. NUMERICAL SIMULATION AND ANALYSIS OF FLOW FIELD AND PARTICLE MOTION IN GRID FLOCCULATION TANK[J]. ENVIRONMENTAL ENGINEERING , 2021, 39(4): 25-29,85. doi: 10.13205/j.hjgc.202104005

Citation:

FU Yu, LONG Yun, XIAO Bo, CHENG Huai-yu, LONG Xin-ping. NUMERICAL SIMULATION AND ANALYSIS OF FLOW FIELD AND PARTICLE MOTION IN GRID FLOCCULATION TANK[J]. ENVIRONMENTAL ENGINEERING , 2021, 39(4): 25-29,85. doi: 10.13205/j.hjgc.202104005

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NUMERICAL SIMULATION AND ANALYSIS OF FLOW FIELD AND PARTICLE MOTION IN GRID FLOCCULATION TANK

doi: 10.13205/j.hjgc.202104005

FU Yu^1,2,
LONG Yun^1,2,
XIAO Bo³,
CHENG Huai-yu^1,2,
LONG Xin-ping^{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;
3. SafBon Water Service Inc, Shanghai 201715, China

Received Date: 2020-05-28
Available Online: 2021-07-21

Abstract

Abstract

Numerical simulation method was used to analyze the characteristics of the internal flow in the front section of the grid flocculation tank. With the vortex velocity gradient and turbulent kinetic energy as the evaluation index of flocculation, the paper verified the rationality of the structural design. In addition, 11 groups of particles with different sizes and effective densities were added to the flow field. Each group randomly released 98560 particles at the entrance of the flow field and their motion was tracked by the DPM model. It was noted that as the particle size increased, the effective density decreased accordingly. The research found that when the particle diameter changed from 1 μm to 1000 μm, the deposition rate was kept less than 10% and the deposition was uniform in each shaft, which could meet the flocculation requirements. When the particle diameter was 1000~5000 μm, the deposition rate increased sharply, but the deposition was uniformed in each shaft. However, when the particle diameter increased to 10000 μm, a large number of particles were deposited in the first shaft, which was not conducive to the uniformity of sludge discharge. So taking deposition rate and the uniformity of sludge discharge into consideration, such large size particles of more than 1000 μm should be avoided in actual engineering practice.
- grid flocculation,
- numerical simulation,
- particle motion,
- DPM model,
- deposition rate

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References(24)

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