Discrete phase model representation of particulate matter (PM) for simulating PM separation by hydrodynamic unit operations.
Discrete phase model representation of particulate matter (PM) for simulating PM separation by hydrodynamic unit operations.
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DOI：
10.1021/es901527r
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发表时间：
2009-10
影响因子：
11.4
通讯作者：
J. Dickenson;J. Sansalone
中科院分区：
文献类型：
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作者：
J. Dickenson;J. Sansalone
自引入澄清降雨径流的单元操作以来，稀颗粒物（PM）分离的建模一直是一个有趣的话题。一个一致但有争议的问题是表征PM和PM分离机制的治疗。在利用牛顿定律和地表溢流率的同时，许多历史模型将PM表示为集总重量指数，这在很大程度上是出于经济考虑和缺乏颗粒分析方法。因此，这些模型不能提供在单元操作中或通过单元操作的粒子命运的信息。在本研究中，应用PM离散相模型（DPM）和计算流体动力学（CFD）来模拟两种常见的流体动力分离器（HS）单元中PM的命运作为粒径和流速的函数。该研究考察了从普通异质分散到单分散PSD的粒度分布（PSD）的离散化要求（作为离散化数，DN）和误差。psd是根据粒度指标进行分类的。结果侧重于确保建模精度，同时检查尺寸分散性和整体PM细度对DN要求的作用。常见的异分散psd的命运在DN为16时被准确预测，而单一粒径指数，通常是d(50m)，被限制在单分散psd，以达到类似的精度。
Modeling the separation of dilute particulate matter (PM) has been a topic of interest since the introduction of unit operations for clarification of rainfall-runoff. One consistent yet controversial issue is the representation of PM and PM separation mechanisms for treatment. While Newton's Law and surface overflow rate were utilized, many historical models represented PM as a lumped gravimetric index largely out of economy and lack of particle analysis methods. As a result such models did not provide information about particle fate in or through a unit operation. In this study, PM discrete phase modeling (DPM) and computational fluid dynamics (CFD) are applied to model PM fate as a function of particle size and flow rate in two common types of hydrodynamic separator (HS) units. The study examines the discretization requirements (as a discretization number, DN) and errors for particle size distributions (PSDs) that range from the common heterodisperse to a monodisperse PSD. PSDs are categorized based on granulometric indices. Results focus on ensuring modeling accuracy while examining the role of size dispersivity and overall PM fineness on DN requirements. The fate of common heterodisperse PSDs is accurately predicted for a DN of 16, whereas a single particle size index, commonly the d(50m), is limited to monodisperse PSDs in order to achieve similar accuracy.