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Inlet Channel Design Program

The purpose of this function is to determine the dimensions of the inlet channel. The channel will run along the inlet end of the sedimentation tanks, such that its length will be equal to the combined widths of all the sedimentation tanks plus the thickness of the walls between the tanks and the thickness of the walls that separate the bays within the sedimentation tank channels. The dimensions of the width and depth of the channel depend on the water level in the sedtank, which should be about the same as in the channel and the flocculator, and the length of the flocculator, since water runs from the end of the flocculator through the channel.

Inlet Channel Design Algorithm

Inlet Channel Program Inputs
Inlet Channel Program Outputs
Inlet Channel AutoCAD Drawing

Algorithm

The primary constraint for designing the channel connecting flocculation and sedimentation tanks is the depth of the channel. The channel must be designed to make sure that the transition between the two tanks does not break up the flocs formed in the flocculation tank.

The length of the channel is a function of the number of sedimentation tanks, and the thickness of the walls between the sedimentation tanks.

Unknown macro: {latex}

\large
$$
L_

Unknown macro: {Channel}

= (N_

Unknown macro: {SedTanks}

)(W_

Unknown macro: {Sed}

) + (N_

+ 1)(T_

Unknown macro: {PlantWall}

)
$$

The cross sectional area of the inlet channel is determined using the A.Port function in Fluids Functions

Unknown macro: {latex}

\large
$$
A_

Unknown macro: {InletChannel}

= A_

Unknown macro: {Port}

(Pi_

Unknown macro: {FlocDissipation}

,K_

Unknown macro: {LTurn90}

,Q_

Unknown macro: {Plant}

,ED_

Unknown macro: {SedInlet}

,Pi_

Unknown macro: {VenaContractaOrifice}

)
$$

The height of the water in the inlet channel is equal to the width of the inlet channel. Therefore the height of the water in the inlet channel is equal to the squareroot of the area of the channel.

Unknown macro: {latex}

\large
$$
W_

Unknown macro: {InletChannelED}

= HW_

Unknown macro: {InletChannel}

$$

Unknown macro: {latex}

\large
$$
HW_

Unknown macro: {InletChannel}

= \sqrt {A_

}
$$

Next the size of the channels that take the flocculated water down into the sedimentation slopes is calculated through the A.Port function in Fluids Functions.

Unknown macro: {latex}

\large
$$
A_

Unknown macro: {SedManifoldEntrance}

= A_

Unknown macro: {Port}

(Pi_

Unknown macro: {FlocDissipation}

,K_

Unknown macro: {PipeEnt}

,Q_

Unknown macro: {SedManifold}

,ED_

Unknown macro: {SedInlet}

,Pi_

Unknown macro: {VenaContractaOrifice}

)
$$

The length of the entrance manifold is set to be equal to the width of the the inlet manifold:

Unknown macro: {latex}

\large
$$
L_

Unknown macro: {SedManifoldEntrance}

= W_

Unknown macro: {SedInlet}

$$

With this value and A.SedManifoldEntrance, the width of the entrance manifold is simple to find:

Unknown macro: {latex}

\large$$
W_

Unknown macro: {SedManifoldEntrance}

= {{A_

} \over {L_

Unknown macro: {SedManifoldEntrance}

}}
$$

We now have two estimates of the required width of the inlet channel. We take the maximum of these two values:

Unknown macro: {latex}

\large
$$
W_

Unknown macro: {InletChanel}

= \max (W_

Unknown macro: {InletChannelED}

,W_

Unknown macro: {SedManifoldEntrance}

+ 2T_

)
$$

The sedimentation manifold port must be the same size as the opening of the sedimentation inlet channel:

Unknown macro: {latex}

\large
$$
W_

Unknown macro: {SedManifoldPort}

= W_

Unknown macro: {SedInlet}

- 2T_

Unknown macro: {SedManifoldEntrance}

$$

Once the width and area are calculated, the height can be easily calculated:

Unknown macro: {latex}

\large
$$
H_

Unknown macro: {SedManifoldPort}

= A_

Unknown macro: {SedManifoldEntrance}

/W_

$$

The height of the inlet channel is equal to the water height in the inlet channel plus the plant freeboard height, so that the water is not at the very top of the channel.

Unknown macro: {latex}

\large
$$
H_

Unknown macro: {InletChannel}

= HW_

+ H_

Unknown macro: {PlantFreeboard}

$$



Unknown macro: {float}

[!InletFront.bmp|width=500px!]



Unknown macro: {float}

[!InletSide.bmp|width=500px!]



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