[1]张世豪,艾恒雨,崔婉莹,等.基于CFD模拟的絮凝效果评价指标研究[J].中国给水排水,2022,38(5):45-53.
　ZHANGShi-hao,AIHeng-yu,CUIWan-ying,et al.Evaluation Indicators of Flocculation Performance Based on CFD Simulation[J].China Water & Wastewater,2022,38(5):45-53.
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基于CFD模拟的絮凝效果评价指标研究

中国给水排水[ISSN:1000-4062/CN:12-1073/TU] 卷: 第38卷 期数: 2022年第5期 页码: 45-53 栏目: 出版日期: 2022-03-01
Title:
Evaluation Indicators of Flocculation Performance Based on CFD Simulation
作者:
张世豪1， 艾恒雨1， 崔婉莹1， 赫俊国2
（1.哈尔滨理工大学 材料科学与化学工程学院，黑龙江 哈尔滨 150040；2.广州大学土木工程学院，广东 广州 510006）
Author(s):
ZHANG　Shi-hao1， AI　Heng-yu1， CUI　Wan-ying1， HE　Jun-guo2
（1. School of Material Science and Chemical Engineering， Harbin University of Science and Technology， Harbin 150040， China； 2. School of Civil Engineering， Guangzhou University， Guangzhou 510006， China）
关键词:
计算流体力学;  絮凝效果;  评价指标;  湍流;  速度梯度
Keywords:
computational fluid dynamics（CFD）;  flocculation performance;  evaluation indicator;  turbulence;  velocity gradient
摘要:
传统絮凝效果评价指标仅是对絮凝工艺作出整体评价，缺乏对絮凝过程的准确描述，不宜作为采用计算流体力学（CFD）软件模拟絮凝效果的评价指标。结合絮凝的动力学过程及流态特征，从水动力学与絮凝形态学两方面探讨了5种评价指标在CFD模拟絮凝过程中的适用性，分析结果表明，絮体的成长尺度和致密程度取决于涡旋速度梯度G’，而欧拉准数Eu则决定着絮凝过程的完善程度，当考察流场总体情况时，同时采用局部G’与Eu两个指标可对絮凝效果作出更为准确的评估；当需要考察输入能量与絮凝效果之间的关系时还应引入湍动能k和湍动能耗散率ε；当评价絮凝设备的有效造涡能力时，可利用后处理获知的流场参数间接计算涡旋尺度λ作为评价指标，尚应考虑速度分布均匀性指标γv，以考察涡旋分布的均匀性；当以絮体的形态作为评价指标时，应将计算流体力学模型与群体平衡模型（PBM）相结合，建立PBM-CFD耦合形式求解。
Abstract:
Traditional evaluation indicators of flocculation performance is only an overall evaluation of the flocculation process, and lacks accurate description of the flocculation process, so it is not suitable to be used as the indicators for flocculation performance evaluation simulated by computational fluid dynamics (CFD) software. Based on the dynamic process and flow characteristics of flocculation, the applicability of five evaluation indicators in CFD simulation of flocculation process was discussed from the aspects of hydrodynamics and flocculation morphology. The growth scale and density of flocs depended on vortex velocity gradient G’, and Euler number Eu determined the perfection of the flocculation process. When the overall flow field was investigated, the flocculation process could be evaluated more accurately by using both local G’ and Eu. Turbulent kinetic energy k and turbulent energy dissipation rate ε should also be introduced to investigate the relationship between energy input and flocculation performance. When evaluating the effective vortex generating capacity of flocculating equipment, the eddy scale λ could be indirectly calculated by using the flow field parameters obtained from post?processing and used as the evaluation indicator, and the uniformity of velocity distribution γv should also be considered to investigate the uniformity of vortex distribution. When the morphology of flocs was used as the evaluation indicator, CFD model should be combined with population equilibrium model (PBM) to establish a PBM-CFD coupling form to solve the problem.

相似文献/References:

[1]谭志程,余健.基于数值模拟的新型合流制溢流调蓄池优化研究[J].中国给水排水,2021,37(23):114.
　TAN Zhi-cheng,YU Jian.Optimization of a Novel Combined Sewer Overflow Storage Tank Based on Numerical Simulation[J].China Water & Wastewater,2021,37(5):114.

更新日期/Last Update: 2022-03-01