Computer Analysis Tool of Hydrosims
SettlerSIMs...A fully Mass Conservative 3-Dimensional Process/Clarifier
Model
Primary and secondary clarifiers are an integral part of the activated sludge
process – crucial components that often determine the success or failure of
the whole treatment system. A clarifier with good performance in one process
may not work well in another process design due to different solids inventory
in different processes. Hydrosims has been using a fully mass conservative
clarifier model in many process retrofit and clarifier trouble shooting projects
world wide to improve design and operation practices. The model-assisted
analysis allows us to predict how the clarifiers would operate under different
conditions. The impact of any design change can be simulated before it is
implemented.
The unsteady three-dimensional models are based on CFD theory. This
unique clarifier model is a powerful tool to evaluate any clarifier designs and
modifications by simulating tank internal hydraulics behavior and sludge
blanket movement. The research of Hydrosims connected with the
development of clarifier model has been published in many technical
journals. Our work is generally recognized as the state of the art by the
international engineering modeling community.
SettlerSIMs...A fully Mass Conservative 3-Dimensional Process/Clarifier
Model
Primary and secondary clarifiers are an integral part of the activated sludge
process – crucial components that often determine the success or failure of
the whole treatment system. A clarifier with good performance in one process
may not work well in another process design due to different solids inventory
in different processes. Hydrosims has been using a fully mass conservative
clarifier model in many process retrofit and clarifier trouble shooting projects
world wide to improve design and operation practices. The model-assisted
analysis allows us to predict how the clarifiers would operate under different
conditions. The impact of any design change can be simulated before it is
implemented.
The unsteady three-dimensional models are based on CFD theory. This
unique clarifier model is a powerful tool to evaluate any clarifier designs and
modifications by simulating tank internal hydraulics behavior and sludge
blanket movement. The research of Hydrosims connected with the
development of clarifier model has been published in many technical
journals. Our work is generally recognized as the state of the art by the
international engineering modeling community.
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SettlerSIMs
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Copyright © 2005-2008 Hydrosims. All rights reserved.
A commercial available CFD package may not be a ready solution
When a commercial available CFD package is going to be selected for
wastewater treatment processes, modelers should notice that the Relative
Density impact (density variations/flow convection) in this area is often much
stronger than that in the applications where the CFD packages were
originally developed and applied for. In addition to the density impact (under
extremely low flow conditions), the mass balance (conservation) at every
time step of model integration has extremely strict requirement.
Some CFD modelers often believe that they are able to obtain clarifier
modeling technology by simply adopting a commercial available
Computational Fluid Dynamic (CFD) package. These modelers most likely
thought they could handle the density impact until they actually include the
density source term in the momentum equation. The strong numerical
instability due to the density variations in their model makes the simulation
convergence almost impossible and forces them to falsely disconnect the
density impact with flow simulations.
When a commercial available CFD package is going to be selected for
wastewater treatment processes, modelers should notice that the Relative
Density impact (density variations/flow convection) in this area is often much
stronger than that in the applications where the CFD packages were
originally developed and applied for. In addition to the density impact (under
extremely low flow conditions), the mass balance (conservation) at every
time step of model integration has extremely strict requirement.
Some CFD modelers often believe that they are able to obtain clarifier
modeling technology by simply adopting a commercial available
Computational Fluid Dynamic (CFD) package. These modelers most likely
thought they could handle the density impact until they actually include the
density source term in the momentum equation. The strong numerical
instability due to the density variations in their model makes the simulation
convergence almost impossible and forces them to falsely disconnect the
density impact with flow simulations.
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Click image for large view
| Existing Clarifier |
| Side View of 3D Clarifier Modeling Results__Flow & Solids Fields |
| Existing Clarifier + MEDIC |