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Table Of Contents
Chapter 5 Working with Hydrology Commands
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To calculate hydraulic values for orifices
1 From the Hydrology menu, choose Orifice Calculator to display the Orifice
Calculator dialog box.
2 From the Solve For list, select the value that you want to calculate. The available
values are: Flowrate, Coefficient, Area or Diameter, Headwater, and Tailwater.
NOTE
Do not enter the value for which you are solving. For example, if you select
Flowrate from the Solve For list, leave the Flowrate text box at 0. After you
enter the other values, the program solves for the Flowrate.
3 Under Use, select Diameter or Area to specify how to calculate the orifice size.
4 In the Flowrate box, type a flow rate for the orifice.
5 In the Coefficient box, type a roughness coefficient for the orifice.
You can also click Select to specify a coefficient from the Orifice coefficient
dialog box. This dialog box describes the orifice shape and the roughness
coefficient value for the shape. For more information, see Specifying an Orifice
Coefficient in this chapter.
6 In the Diameter box, type the diameter for the orifice.
NOTE
The diameter text box is available only if you selected Diameter in step 3.
You can also click Select to specify the diameter by selecting points on the
drawing. For more information, see Specifying a Diameter in this chapter.
7 In the Area box, type the area for the orifice.
NOTE
The area text box is available only if you select Area in step 3.
You can also click Select to specify the area by selecting points on the drawing.
For more information, see Specifying an Area in this chapter.