Effects of Hydraulic Head and Emitter on the Soil Water Movement under Negative Pressure Irrigation System
Abstract：A series 1aboratory experiments were arranged to study the effects of different water head（H=0.5,0,-0.5,-1,-2 m）and emitters（emitter aperture of 3~4 μm and 5~6 μm） on the soil water movement and efficiency of negatively pressurized irrigation system.A 30° wedge-shaped Plexiglas container was used to represent one twelfth of the complete cylinder.The results show that the wetting fronts have a same movement regular pattern and the wetting body is almost ellipsoid-shaped under different treatments.Volume of wetting body decreases with the decrease of hydraulic heads during same irrigation time.The relationships between time and cumulative infiltration,the maximum horizontal and vertical wetted distances are power functions.During the same period,when H=0.5,0,-0.5 m,the emitter aperture of 5~6 μm has higher efficiency,but when H=-1 m,-2 m,the emitter aperture of 3~4 μm has higher efficiency.
Keywords：negative pressure irrigationwetting frontcumulative infiltrationnegative pressure emitter
Publication Date：2011-01-01
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)