Submitted to: Irrigation Business and Technology Magazine
Publication Type: Trade Journal
Publication Acceptance Date: August 1, 1996
Publication Date: N/A
Interpretive Summary: Center pivot and traveling lateral irrigation systems are used on about 11 million acres in the U.S. Users of these systems now have a wide array of sprinkler packages to choose from, including the traditional overhead impact sprinklers, various types of spray heads and LEPA-type furrow emitters. Recently, rotating plate or wobble-plate spray heads have been developed, allowing larger sprinkler spacings with lower peak application rates at medium to low pressures (10 to 30 psi). Uniformity coefficients of about 0.95 can be achieved if recommended spacing limits are observed; however, field uniformities will be slightly lower due to topographic effects and other factors.
Technical Abstract: This article describes an automated test setup for measuring sprinkler patterns in wind, and shows how the data can be applied to the types of spray devices now used on center pivot and lateral move sprinkler systems. Uniformity of application, average and peak application rates, are affected by windspeed and direction and sprinkler spacing and elevation. These effects are analyzed with the help of 3-D graphics and computer simulation. Maximum recommended sprinkler spacings are given, along with a discussion of other factors which can affect field uniformity.