الفهرس 
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Abstract
Three experiments had been conducted; the first was a laboratory
calibration to examine some hydraulic specifications of five emitter types
(Em1, Em2, Em3, Em4; Em5). The second was hydraulic evaluation, for
three emitters selected from laboratory experiment (Em1, Em3; Em5) at
short lateral lengths (20, 30; 40 m) under low operating pressure (20 kPa),
in two different subunit layouts: unconnected lateral ends or/ open loop
(OL) and connected lateral ends or/ closed loop (CL), using groundwater
as an irrigation water source. Em1 and Em3 were imported with pressure
compensating (self-flushing mechanism) and turbulent flow, respectively.
While Em5 type was locally manufactured with turbulent flow regime.
Finally, the third field evaluation experiment was to study the effect of
clogging on the previous three emitters during the season of cantaloupe
crop.
Em5 had unacceptable coefficient of variation values and low
distribution uniformity of water, moreover the massive water and energy
consumption. The measured or/ actual discharges for most emitter types
were excess than the nominal discharge under 100 kPa operating
pressure, by these percentages: 6.93, 0.0, 5.5, 165, and 640% for Em1,
Em2, Em3, Em4, and Em5, respectively.
Em1 and Em3 tested emitters were ideally suitable for (20, 30; 40
m) lateral lengths under low operating pressure (20 kPa), rather than Em5
type. The use of CL drip layout raises the DU and decreases the pvar and
qvar in comparison with OL.
The clogging influenced the three emitter types; Em1 and Em5
showed the highest anti-clogging performance in comparison to Em3
type.