Invented in 1948, Center Pivot Irrigation has grown to become the backbone of the food production industry. Surprisingly, design of this widely used agricultural irrigation technique tends to be carried out in the same way as it was back then: with pencil-and-paper drawings and manual calculations. Irrigation brings Center Pivot Irrigation into the 21st century. Our Center Pivot Irrigation tool offers an intuitive interface and automatic calculations of factors such as precip rates and run times.
Center Pivot Irrigation Overview
Open the Center Pivot Irrigation tool:
F/X Irrigation ribbon, Center Pivot flyout
Type CenterPivot in the Command line
F/X Irrigation menu, Center Pivot option
The Center Pivot Designer dialog box will open. Here, you can configure and place each Center Pivot area you need for your site.
Adding and Placing Center Pivot Areas
In the Center Pivot Designer dialog box, select a spray pattern (example: Full or Part Circle), and enter a spray Radius. Then click OK.
The data you need to set at this point will vary slightly, depending on the pattern you've selected. For example, the End Gun and/or Overhang option will require you to enter a Gun Distance (in feet or meters) and a Gun Angle (in degrees), in addition to the Radius.
The Center Pivot pattern you selected will now appear at the AutoCAD crosshairs. Click two points to set your spray arc.
In our example, we'll set a 90-degree spray arc by clicking once at a point straight down in the drawing from the pivot point ...
... and then clicking another point straight to the right of the pivot point.
Once you've set the extent of your center pivot arc, the Center Pivot Calculator dialog box will open. This dialog box performs automatic calculations of the necessary runtime, end tower speed, and pressure required to provide the proper coverage for the area and precipitation rate you set. Configure your settings, and click OK.
1 The Area (in square feet or meters) of your coverage arc is pre-calculated based on the settings you've provided (such as Radius) and the arc pattern you've set. You can change this number as needed.
2 Enter your desired Precip Rate (in inches or centimeters per hour). The rest of the data will calculate automatically based on the rate you've set.
3 The Run Time in hours required for the Precip Rate you've set.
4 The End Tower Speed (in feet or meters per minute) required for your Precip Rate and Run Time.
5 The flow rate (in GPM or MPM) required for the other settings.
Automatic calculations figure heavily into our Center Pivot Irrigation tool. Each of the entries in the Center Pivot Calculator dialog box is dependent on the values you've set for the others. As you change one value and then another, you'll notice the other values changing to meet the needs of each requirement you set for your system. Play around with these numbers until you reach the exact setting you need.
Once you click OK, the Center Pivot Span Configuration dialog box will open. Click the ... button to the right of the Manufacturer field to select a manufacturer.
The Select Manufacturer dialog box will open. Select a manufacturer.
The Select Series dialog box will open. Select a series of Center Pivot system offered by the manufacturer you chose.
You'll now see the manufacturer and series you selected in the Manufacturer field. Select a Number of Spans from the menu, and select any other necessary data in the menus below. Then click OK.
The Center Pivot area you configured will now appear in your drawing. Here's the 90-degree arc we set:
When you zoom in, you'll see a symbol for the Center Pivot system at the pivot point of the arc.
The data you set in the calculation dialog box will appear within the arc for quick reference. This includes:
- Area
- Precip rate
- Run time
- End tower speed
- Flow rate
Related Webinars
- Center Pivot Design: Land F/X CEO and head developer Jeremiah Farmer shows off our Center Pivot irrigation tool, which automates this technique that's become no less than a mainstay of feeding the planet since its inception in 1948. (1 hr 6 min)
