Manhole Simple Loss Example: Difference between revisions
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==Example 3: Multiple Incoming Conduits with Incoming Bend and Drop in Invert Levels==
In this example we have multiple incoming conduit. Each upstream conduit has a flow of 1m<sup>3</sup>s<sup>-1</sup> applied to it.<br>
[[File:Schematic 3.png|800px]]
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|'''Downstream Invert Level (m AD)''' || 99.7 || 99.8
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The resulting simulated loss values are presented in Figure 8.
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===Example 3 - Entry Losses===
This time the flow area in the manhole is 3.57m<sup>2</sup> and 1m<sup>2</sup> in the adjacent culvert whilst the flow is 1m<sup>3</sup>/s for Q<sub>p</sub> and 2m<sup>3</sup>s<sup>-1</sup> for Q<sub>om</sub>. Therefore, V<sub>m</sub> equals:[[File:Vm3.PNG]]▼
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▲This time the flow area in the manhole is 3.57m<sup>2</sup> and 1m<sup>2</sup> in the adjacent culvert whilst the flow is 1m<sup>3</sup>/s for Q<sub>p</sub> and 2m<sup>3</sup>s<sup>-1</sup> for Q<sub>om</sub>. Therefore, V<sub>m</sub> equals:<br>[[File:Vm3.PNG]]
And V<sub>p</sub>:[[File:Vp3.PNG]]▼
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▲And V<sub>p</sub>:<br>[[File:Vp3.PNG]]
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From this:<br>
[[File:K entry3.PNG]]<br>
This matches the losses for both incoming pipes as shown in figure 8.
===Example 3 - Exit Losses===
A'<sub>m</sub> is 3.57m<sup>2</sup> respectively. Therefore, K<sup>exit</sup>:<br>[[File:K exit3.PNG]]<br>
The calculated losses match the losses calculated by the TUFLOW presented in Figure 8.<br>
===Example 3 - Outgoing Conduit Losses===<br>
In this model we have two incoming pipes, one with an 90 degree angle between the incoming and outgoing conduit and one with zero.
Recall that: <br>[[File:Ktheta.PNG]]<br>
With Qf calculated as: <br>[[File:Qf.PNG]]
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Q<sub>p</sub> is set to 1m<sup>3</sup>s<sup>-1</sup> and Q<sub>om</sub> to 2m<sup>3</sup>s<sup>-1</sup>. Q<sub>f</sub> is equal to 0.5m<sup>3</sup>s<sup>-1</sup>. For the incoming conduit with an angle of 90 degrees, K<sub>θ</sub> is therefore: <br>[[File:Ktheta2a.PNG]]<br>
For the incoming conduit with an angle of 0 degrees, K<sub>θ</sub> is therefore: <br>[[File:Ktheta2b.PNG]]<br>
We also have a drop between the incoming and outgoing pipes. K<sub>drop</sub> which represents losses due to this drop is calculated as follows: <br>[[File:Kdrop 2a.PNG]]
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and:<br>[[File:Kdrop 2b.PNG]]<br>
Therefore, K<sub>outletpipe</sub> is: <br>[[File:K outletpipe3.PNG]]<br>
The calculated value matches that presented in figure 8 for the downstream conduit loss.
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