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Table Of Contents
Calculating Pipe Flow and Other Hydraulic Values Using the Darcy-Weisbach Equations
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Calculating the Flow for Circular Pipes Using the
Darcy-Weisbach Equations
To calculate the flow for circular pipes using the Darcy-Weisbach formula
1 From the Hydrology menu, choose Pipes ä Darcy-Weisbach Circular to display
the Darcy-Weisbach Calculator dialog box.
2 From the Solve For list, select the value you want to calculate.
The available values are: Flowrate, Length, Headloss, Friction Factor, and
Diameter.
NOTE
Do not enter the value for which you are solving. For example, if you select
Flowrate in this step, leave the Flowrate text box at 0. After you enter the
other values, the program solves for the Flowrate. Also, if you are solving
for diameter, you must enter a value in the Diameter edit box to start
calculations.
The following illustration shows circular pipe values:
Circular pipe values
3 In the Flowrate box, type a flow rate for the pipe (unless you are solving for the
flowrate).
4 In the Length box, type a length for the pipe (unless you are solving for the
length).
You can also click Select to specify the length by selecting an object or points
on the drawing. For more information, see Specifying a Length in this
chapter.
5 In the Headloss box, type a value to account for headloss (unless you are solving
for the headloss).
You can also click Select to specify the headloss value by selecting an object or
points on the drawing. For more information, see Specifying a Headloss Value
in this chapter.
6 In the Friction Factor box, type a friction factor value for the selected pipe
(unless you are solving for the friction factor).
You can also click Select to display the Darcy-Weisbach Friction Factors dialog
box and select a coefficient. This dialog box describes the pipe and its
coefficient value. For more information, see Specifying a Darcy Weisbach
Roughness Coefficient in this chapter.