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Table Of Contents
Calculating Pipe Flow and Other Hydraulic Values by Using the Hazen-Williams Equations
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the pipe is calculated and displayed at the bottom left of the dialog box. This
information is for display only and cannot be edited.
NOTE
If the data you entered has an error, the pipe graphic image does not
display. Check for an error message at the bottom of the dialog box.
9 Click OK to exit the dialog box.
Calculating Pipe Flow and Other Hydraulic
Values by Using the Hazen-Williams Equations
The Hazen-Williams pipe calculators calculate flowrates and other hydraulic
variables for pipes. The Hazen-Williams formula is used when a pipe is in
pressure flow. The different menu items provide the variation for the shape of
the pipe: Circular, Rectangular, Elliptical, or Custom (User).
Hazen-Williams Formula
The commands on the Hazen-Williams menu calculate piping values. The
Hazen-Williams formula used to calculate head loss due to friction in circular
pipes is:
Metric:
VcRS 0849
063 054
.
..
Imperial:
VcRS 1318
063 054
.
..
where:
V = Fluid velocity
c = Roughness coefficient
R = Hydraulic radius
S = Head loss due to friction
Calculating the Flow for Circular Pipes Using the
Hazen-Williams Equations
To calculate circular piping values using the Hazen-Williams equations
1 From the Hydrology menu, choose Pipes ä Hazen-Williams Circular to display
the Hazen-Williams dialog box.
2 From the Solve For list, select the value you want to calculate. The available
values are: Flowrate, Length, Headloss, Coefficient, 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.