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King, B.A.; Winward, T.W.; Bjorneberg, D.L.. |
Kinetic energy of water droplets has a substantial effect on development of a soil surface seal and infiltration rate of bare soil. Methods for measuring sprinkler droplet size and velocity needed to calculate droplet kinetic energy have been developed and tested over the past 50 years, each with advantages, disadvantages, and limitations. A laser precipitation meter and photographic method were used to measure droplet size and velocity from an impact sprinkler at three pressures and one nozzle size. Significant differences in cumulative volume drop size distributions derived from the two measurement methods were found, especially at the highest operating pressure. Significant differences in droplet velocities were found between measurement methods as... |
Tipo: Conference or Workshop Item |
Palavras-chave: Sprinkler irrigation; Soil water (soil moisture); Water management. |
Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1577/1/1533.pdf |
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Winward, T.W.; Hill, R.W.. |
A line-source sprinkler configuration provides a linearly decreasing irrigation application rate perpendicular to the sprinkler line and has been utilized to study crop response to variable irrigation amounts. The effect on measured irrigation application depths from using various types of catch-cans in those studies is not known. Derived relationships between crop yield and applied water is dependent on the accuracy of measured catch-can water volumes. The purpose of this study was to evaluate catch-can characteristic effects on measurement of sprinkler irrigation depths in a line source. This was accomplished by evaluating six types of catch-cans: (1) 83 mm diameter polypropylene separatory funnel (with evaporation-suppressing oil), (2) 82 mm... |
Tipo: Article |
Palavras-chave: Sprinkler irrigation; Mass Import - autoclassified (may be erroneous). |
Ano: 2007 |
URL: http://eprints.nwisrl.ars.usda.gov/63/1/1228.pdf |
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King, B.A.; Winward, T.W.; Bjorneberg, D.L.. |
Sprinkler drop size distribution and associated drop velocities have a major influence on sprinkler performance in regards to application intensity, uniformity of water application, wind drift, evaporation losses and kinetic energy transferred to the soil surface. Sprinkler drop size measurements are either labor intensive or require use of expensive equipment, both of which limit data availability. Sprinkler drop velocity data are more limited than drop size data due to measurement difficulty and associated cost of labor and instrumentation. An economical laser instrument commercially marketed for real-time rainfall measurements as a Laser Precipitation Monitor (LPM) was used to measure drop size and velocity from ten moving spray-plate type... |
Tipo: Article |
Palavras-chave: Irrigation control; Sprinkler irrigation. |
Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1564/1/1520.pdf |
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King, B.A.; Winward, T.W.; Bjorneberg, D.L.. |
Kinetic energy of water droplets has a substantial effect on development of a soil surface seal and infiltration rate of bare soil. Methods for measuring sprinkler droplet size and velocity needed to calculate droplet kinetic energy have been developed and tested over the past 50 years, each with advantages, disadvantages, and limitations. Drop size and velocity of an impact sprinkler at three operating pressures and one nozzle size were measured using a laser precipitation meter and compared with published values obtained using a photographic method. Significant differences in cumulative volume drop size distributions derived from the two measurement methods were found, especially at the highest operating pressure. Significant differences in droplet... |
Tipo: Article |
Palavras-chave: Sprinkler irrigation. |
Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1543/1/1500.pdf |
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King, B.A.; Winward, T.W.; Bjorneberg, D.L.; Wall, R.W.. |
Peak water application rate in relation to soil water infiltration rate and soil surface storage capacity is important in the design of center pivot sprinkler irrigation systems for efficient irrigation and soil erosion control. Measurement of application rates of center pivot irrigation systems has traditionally used tipping bucket rain gauges. Calculation of application rate from tipping bucket rain gauge measurements restricts computed application rate to a discrete multiple of the rain gauge resolution and time interval. This limits the resolution of application rate measurement, especially for time intervals less than 15 minutes. A collector was designed to measure time variant high intensity sprinkler application rates under field conditions with... |
Tipo: Article |
Palavras-chave: Sprinkler irrigation; Soil; Water. |
Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1565/1/1521.pdf |
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