الفهرس 
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Abstract
Evaluation of drip irrigation components will provide useful information for
de igners ,operators and farmers using drip irrigation system . Therefore the aim
of this work is to investigate the technical and economical parameters for the
m in components of drip irrigation in Egypt for both locally made and imported
ite s, through the following studies .
a - Evaluation of emitters: - The evaluation parameters were:
1 - Determination of discharge equation constants.
2 - Determination of the coefficient of manufacturing variation.
b - valua1ion offilters : For media filter die evalua1ion pal’alllderswere:
1 - Head losses across the filter ( ill )
2 - Accumulated quantity of water flow through the filter (nr’ )
3 - filteration Efficiency %
For screen and Disc filters: Three types are used for evaluation.
Two local manufactured screen types of 40 m3./h max.
capacity and the third one was of disc type ( imported) .
the experimental measurements was carried out to obtain the head losses
across the filter under different flow rates .
ation of fertilizers devices : Three different types namely, injection
p p. Venturi and pressure tank , and two mixtures of chemical fertilizers
we e used in this study the evaluation parameters were :
1 - The fertilizer concentration in the irrigation water ( ppm ) .
2 - Fertilizing time ( min. )
3 - Injection rate of fertilizers ( lIh ) .
d- Economics of drip irrigation system:
An area of ten feddans was taken to compare the cost of locally and
imported components which used in Egypt.
The experiments were carried out at EI-Harm greenhouses site, Rashied,
Dahshour , Gezerate El-Dahab and Extension field in Ismailia, in 1994 and
1995 .
• Discharge - pressure relationship :
Twenty different types of emitters were hydraulically tested and evalated .
Six emitters from each type were tested under pressure 0.05, 0.10,0.15 and 0.20
Mpa . The emitters were operated for two minutes .
The corresponding average flow rate (q) values, were plotted against (h)
on log - log paper to determine values of (k) and (X) . Discharge of all tested
emitter ( long path , vortex and orifice types ) ranged between 1.74 to 30 IJh
according to the emitter type and operating pressure . The results indicate, the
discharge of emitters increased with increasing the operating pressure . Values of
X ranged between 0.72 to 0.14. Most of the tested emitters have X values mostly
in the range of 0.25 to 0.50 which indicate that the flow is fully to partially
turbulent and provides low variation in discharge With considerable variation in
pressure. For vortex type a flow regime approaching laminar, for which X> 0.70
( Bezdek and Solomon 1978) , this types of emitters ( vortex type) require
shorter lengths or larger diameters of lateral pipeline and should not be
recommended for irrigating steep slopes.
For compensating emitters ,( X approaches zero) the discharge remains
nearly constant with variation in pressure head.
oJ< Coefficient of Manufacturer’s Variation (CV) :
The results showed that there are three types of locally manufactured
emitters classified as a not acceptable emitters ( CV > 0.15 ) , so they may not be
reconunended for use in intensive agriculture projects. Ten imported and one
local types of emitters are good ( 0.05 < CV < 0.1 ) . Six types of imported
emitters classified as ” very good ” .
* Evaluation of filters: The results indicated that, head losses across the
filter increased with increasing flow accumulation through the filter and the
filtration efficiency decreased with increasing head losses across the filter. With
increasing operating time the accumulated quantity of water increased but both
the slope ( mean flow rate m3 Ih ) and the removal efficiency decreased .
This general result was obtained in all tested filter . These results were
expected due to increasing the sedimentation concentrate ( gm I I ) on the media
surface . Taking the imported vertical type filter as an example it could be
observed that, increasing the accumulated quantity of water delivered through the
filter from 597 to 1045 m3 respectively. (75 % increase) , the corresponding
head losses across the filter were increased from 3.27 to 7.10 m respectively (
117 % increase) . Consequently , the filtration efficiency decreased from 700/0 to
60% respectively .Comparing the results for the tested three types of media
filters, it could be stated that, the vertical ( imported ) filter gave better
performance, since it has less head losses and higher removal efficiency than the
other two types of filters ( imported horizontal and locally made vertical filters)
when evaluated under the same operating conditions .
For screen or disc filters: , the results indicate”that, the flow rate increased
from 10 to 40 m3 Ih the head losses acress the filters increased from 0.10 to
• Capitall Cost of drip irrigation system :
The results indicate that, using locally produced components saves almost
750/0 compared with the cost of simillar size imported items, for trees but for
vegetables crop using locally produced components saves ahnost 71% compared
with the imported items, of simillar size but not quality or efficiency .
In general it may be concluded that improving the quality of locally
produced components is justify this large difference in cost. On other hand, low
quality locally materials may be not recommended for intensive, sensitive , high
cash crop production, since these crops needs high level of water control and
uniformity of distribution as well as optimum fertilization rate and timing.