h1. CFD Sedimentation Tank Simulation


h2. Overview

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[!sedimentation tank manifold design.jpg|width=200px!|CFD Sedimentation Tank Simulation]
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To model the flow (experimentally/computationally) distribution in the bottom of a sedimentation tank, and to devise an optimal design for creating uniform flow.

CFD Sedimentation Tank Simulation [goals|CFD STS Goals] and [meeting minutes|CFD STS Meeting Minutes].


h2. Problem Specification

h4. Existing Design

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[!existing design.jpg|width=200px!|CFD Sedimentation Tank Simulation]
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In the latest design of sedimentation tank, we use a V-shaped tank bottom to collect and drain the settled flocs, with influent pipes installed along the slopes.

h4. Changes and Challenges

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[!modified design.jpg|width=200px!|CFD Sedimentation Tank Simulation]
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In a newly proposed design, we will make better use of the space under the surface of V-shaped bottom, replacing the concrete with void space for influent water, and create water inlet at the bottom of the slopes. In this new design, we use less concrete and less pipes to bring down the cost, and avoid the unstability of upward flow caused by multiple pipes at the bottom.

The major challenge in this new design is how to configure geometry of the water inlet at the bottom of the slopes to create flows as uniform as possible.

h4. Primitive Ideas

Intuitively, there are three basic situations of the water inlets.

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[!collision region.jpg|width=200px!|CFD Sedimentation Tank Simulation]
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h5. Water from both sides (collision region)
Openings for water inlets on bothsides. Water flows from both sides, collide with each other and rise in the middle.

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[!single flow region.jpg|width=200px!|CFD Sedimentation Tank Simulation]low region.
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h5. Water from one side (single flow)
Opening for water inlets on one side. Water flows from one side, collide and rise along with the slope on the other side.