Improved Equations for Estimating Spray Losses of Fixed Sprinkler Irrigation Systems in Iraq

Abstract

Many local field studies on sprinkler spray losses in Iraq have been conducted, the first was in 1980 and the latest is in 2008. Many equations to estimate these losses have been proposed. But, most of these studies depended on narrow ranges in the values of the parameters and variables involved. Therefore, there may be great risk in applying these equations in the design and management of sprinkler irrigation systems. Add to that, the problem of unavailability of data for some of the variables involved which makes the use of these equations impossible. Thus, this study presented a group of 14 prediction equations for the sprinkler spray losses, so that it becomes possible to estimate these losses if one or more of the following main variables is available: air temperature, wind speed, relative humidity, nozzle size, and operating pressure head. The derivation of the proposed equations depends on all available local field data, thus making these equations more accurate and general. Key words: Sprinkler irrigation, sprinkler spray losses, sprinkler irrigation in Iraq.