Stormwater treatment： examples of computational fluid dynamics modeling
Control of rainfall-runoff particulate matter （PM） and PM-bound chemical loads is challenging; in part due to the wide gradation of PM complex geometries of many unit operations and variable flow rates. Such challenges and the expense associated with resolving such challenges have led to the relativ...
Saved in:
| Published in: | Frontiers of Environmental Science & Engineering Vol. 6; no. 5; pp. 638 - 648 |
|---|---|
| Main Authors: | , , , , , , |
| Format: | Journal Article |
| Language: | English |
| Published: |
Heidelberg
Higher Education Press
01.10.2012
SP Higher Education Press Springer Nature B.V |
| Subjects: | |
| ISSN: | 2095-2201, 2095-221X, 1673-7520 |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Control of rainfall-runoff particulate matter （PM） and PM-bound chemical loads is challenging; in part due to the wide gradation of PM complex geometries of many unit operations and variable flow rates. Such challenges and the expense associated with resolving such challenges have led to the relatively common examination of a spectrum of unit operations and processes. This study applies the principles of computa- tional fluid dynamics （CFD） to predict the particle and pollutant clarification behavior of these systems subject to dilute multiphase flows, typical of rainfall-runoff, within computationally reasonable limits, to a scientifically acceptable degree of accuracy. The Navier-Stokes （NS） system of nonlinear partial differential equations for multi- phase hydrodynamics and separation of entrained particles are solved numerically over the unit operation control volume with the boundary and initial conditions defined and then solved numerically until the desired convergence criteria are met. Flow rates examined are scaled based on sizing of common unit operations such as hydrodynamic separators （HS）, wet basins, or filters, and are examined from 1 to 100 percent of the system maximum hydraulic operating flow rate. A standard turbulence model is used to resolve flow, and a discrete phase model （DPM） is utilized to examine the particle clarification response. CFD results closely follow physical model results across the entire range of flow rates. Post-processing the CFD predictions provides an in-depth insight into the mechanistic behavior of unit operations by means of three dimensional （3-D） hydraulic profiles and particle trajectories. Results demon- strate the role of scour in the rapid degradation of unit operations that are not maintained. Comparisons are provided between measured and CFD modeled results and a mass balance error is identified. CFD is arguably the most powerful tool available for our profession since continuous simulation modeling. |
|---|---|
| Bibliography: | stormwater, unit operations and processes（UOPs）, hydrodynamic separation, filtration, adsorption,computational fluid dynamics （CFD）, turbulence modeling,discrete phase model, particle separation, detention/reten-tion basins, clarification Control of rainfall-runoff particulate matter （PM） and PM-bound chemical loads is challenging; in part due to the wide gradation of PM complex geometries of many unit operations and variable flow rates. Such challenges and the expense associated with resolving such challenges have led to the relatively common examination of a spectrum of unit operations and processes. This study applies the principles of computa- tional fluid dynamics （CFD） to predict the particle and pollutant clarification behavior of these systems subject to dilute multiphase flows, typical of rainfall-runoff, within computationally reasonable limits, to a scientifically acceptable degree of accuracy. The Navier-Stokes （NS） system of nonlinear partial differential equations for multi- phase hydrodynamics and separation of entrained particles are solved numerically over the unit operation control volume with the boundary and initial conditions defined and then solved numerically until the desired convergence criteria are met. Flow rates examined are scaled based on sizing of common unit operations such as hydrodynamic separators （HS）, wet basins, or filters, and are examined from 1 to 100 percent of the system maximum hydraulic operating flow rate. A standard turbulence model is used to resolve flow, and a discrete phase model （DPM） is utilized to examine the particle clarification response. CFD results closely follow physical model results across the entire range of flow rates. Post-processing the CFD predictions provides an in-depth insight into the mechanistic behavior of unit operations by means of three dimensional （3-D） hydraulic profiles and particle trajectories. Results demon- strate the role of scour in the rapid degradation of unit operations that are not maintained. Comparisons are provided between measured and CFD modeled results and a mass balance error is identified. CFD is arguably the most powerful tool available for our profession since continuous simulation modeling. 10-1013/X computational fluid dynamics (CFD) discrete phase model adsorption unit operations and processes (UOPs) turbulence modeling clarification stormwater Document received on :2012-01-20 filtration Document accepted on :2012-07-05 particle separation hydrodynamic separation detention/retention basins ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 14 content type line 23 |
| ISSN: | 2095-2201 2095-221X 1673-7520 |
| DOI: | 10.1007/s11783-012-0442-7 |