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Optimal design of drip irrigation submains: presure-compensating emitters

Abstract

For a drip irrigation system to be successful, it must he well designed, properly installed, managed and maintained. In plots with steep slopes and irregular topography that have little land leveling capacity and/or that require very efficient agricultural machinery, drip irrigation designs generally use pressure-compensating emitters. This work develops a methodology and implements it in a computer tool that makes it possible to optimally determine in drip-irrigated plots with pressure-compensating emitters: a) telescopic sizing of the submain manifold pipe, b) supply valve pressure and c) subunit''s intake valve location, when considering all hydraulic-economic aspects in the design phase. Techniques of optimal sizing of pipe networks and simulation of hydraulic networks under pressure are linked to economic analyzes of total annualized costs. Finally, the practical usefulness of the proposed methodology is shown with three examples of complex real cases where pipe design costs are reduced by 16-34% and energy costs by 37-51%. Sicoli, C.E.S.; Aliod, R.; Zorilla, F.; Morabito, J.A.

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Optimal design of drip irrigation submains: presure-compensating emitters

Author: Sicoli, C.E.S.; Zorilla, F.; Morabito, J.A.; Aliod, R.
Year: 2019
Source: https://zaguan.unizar.es/record/99402/files/texto_completo.pdf
154 Re is a de la Facul ad de Ciencias Ag a ias
C. E. Schila di Sícoli e al.
Op imal design o d ip i iga ion submains:
p esu e-compensa ing emi e s
Diseño óp imo de sec o es de iego po go eo:
emiso es au ocompensados
Ca los E. Schila di Sícoli 1 *, Rica do Aliod 2, Fe nando Zo illa 2, José An onio Mo ábi o 1, 3
O iginales: Recepción: 26/03/2018 - Acep ación: 18/05/2019
Abs ac
Fo a d ip i iga ion sys em o be success ul, i mus be well designed, p ope ly
ins alled, managed and main ained. In plo s wi h s eep slopes and i egula opog aphy
ha ha e li le land le eling capaci y and/o ha equi e e y e icien ag icul u al
machine y, d ip i iga ion designs gene ally use p essu e-compensa ing emi e s.
This wo k de elops a me hodology and implemen s i in a compu e ool ha makes
i possible o op imally de e mine in d ip-i iga ed plo s wi h p essu e-compensa ing
emi e s: a) elescopic sizing o he submain mani old pipe, b) supply al e p essu e
and c) subuni ’s in ake al e loca ion, when conside ing all hyd aulic-economic aspec s
in he design phase. Techniques o op imal sizing o pipe ne wo ks and simula ion o
hyd aulic ne wo ks unde p essu e a e linked o economic analyzes o o al annualized
cos s. Finally, he p ac ical use ulness o he p oposed me hodology is shown wi h h ee
examples o complex eal cases whe e pipe design cos s a e educed by 16-34% and
ene gy cos s by 37-51%.
Keywo ds
d ip i iga ion • design • submain • p essu e-compensa ing emi e s
1 Uni e sidad Nacional de Cuyo. Facul ad de Ciencias Ag a ias. Almi an e B own
500. Luján. C. P. M5528AHB. Mendoza. A gen ina. * cschila di@ ca.uncu.edu.a
2 Uni e sidad de Za agoza. Escuela Poli écnica Supe io de Huesca (EPSH).
Ca e e a de Cua e S/N. C. P. 22071. Huesca. España.
3 Cen o Regional Andino. Ins i u o Nacional del Agua. Belg ano 210 Oes e
(M55500FIF). Mendoza. A gen ina.
Re . FCA UNCUYO. 2019. 51(2): 154-166. ISSN (en línea) 1853-8665.
155
Tomo 51 • N° 2 • 2019
Op imal design o d ip i iga ion submains: P esu e-Compensa ing Emi e s
Resumen
Pa a que un sis ema de iego po go eo enga éxi o, debe es a bien diseñado, adecua-
damen e ins alado, ap opiadamen e manejado y man enido. En pa celas con g andes
pendien es, opog a ía i egula , con poca capacidad de ni elación y/o en si uaciones
donde se p e ende ene una al a e iciencia de la maquina ia ag ícola, los diseños de
iego po go eo gene almen e ecu en a la u ilización de emiso es au ocompensan es.
El p esen e abajo desa olla una me odología y ealiza su implemen ación en una
he amien a in o má ica que pe mi e en sec o es de iego po go eo con emiso es
au ocompensan es de e mina de mane a óp ima: a) el dimensionado elescópico de la
ube ía secunda ia (po a-la e ales), b) la p esión en ál ula de alimen ación del sec o
y c) el pun o de alimen ación del sec o (ubicación de dicha ál ula); conside ando
odos los aspec os hid áulicos-económicos in oluc ados en la ase de diseño. Pa a ello,
se inculan écnicas de dimensionado óp imo de conducciones y simulación hid áulica
de edes a p esión con análisis económicos de cos os o ales anualizados. Finalmen e,
se demues a la u ilidad p ác ica de la me odología desa ollada median e ejemplos
eales de aplicación, donde los cos os de diseño se educen en e 16-34% y los cos os de
ene gía en e 37-51%.
Palab as cla e
iego po go eo • diseño • subunidades • emiso es au ocompensan es
In oduc ion
The success o a d ip i iga ion sys em
depends essen ially on p ope design,
selec ion and ins alla ion (25) and co ec
managemen and main enance (12). In
o de o ensu e i s inancial sus ainabili y,
he bene i o he i iga ed c op mus
co e he high capi al cos s which his
me hod en ails (17). Op imal design o
d ip i iga ion is impo an o inc ease he
in es men s in and bene i s de i ed om
i iga ion (16). Such design should aim a
minimizing o al annualized piping and
ene gy cos s (32, 33) and ensu ing wa e
dis ibu ion uni o mi y (4, 6, 17, 19)
In s eep slope plo s (20) wi h i egula
opog aphy and li le land le eling capaci y
and/o ha equi e highly e icien ag icul-
u al machine y, d ip i iga ion sys ems
gene ally use p essu e-compensa ing
emi e s. They deli e a p ac ically cons an
discha ge o e a wide ange o p essu es
(20, 21, 35), called e ec i e p essu e
compensa ion ange, be ween 5 and 35 m,
and can lowe he limi s by ± 2 o aise hem
by ± 5 m (3), depending on each manu ac-
u e . P essu e egula ion is achie ed by
means o an elas ic memb ane ha co e s
he low pa h (36). A p essu e-compen-
sa ing emi e can be desc ibed by he
ollowing p essu e-discha ge unc ion (26):
(1)
whe e:
q = low o he emi e [L] 3 [T] -1
K = cha ac e is ic discha ge coe icien
o he emi e [L] 3-x [T] -1
h = emi e p essu e [L]
x = emi e discha ge exponen
q0 = cons an discha ge o he compen-
sa ion ange [L] 3 [T] -1
0
0 0 max
,0
,
x
kh h h
qq h h h

〈 ≤
〈 〈

156 Re is a de la Facul ad de Ciencias Ag a ias
C. E. Schila di Sícoli e al.
h0 = minimum p essu e o he compen-
sa ion ange [L]; his is de ined as:
(2)
Fo a good p essu e compensa ing
emi e , mos designe s will y o keep he
p essu es h oughou he ield in a ange
be ween 7-24.5 m (5). Mon al o (2005)
ecommends o sa e y easons a minimum
p essu e alue o he emi e ha is a
leas 2 m highe han he lowe limi o
he compensa ion ange and a maximum
p essu e o 25 m. I is necessa y o keep
p essu es wi hin ha ange o a oid: a)
disconnec ion o he d ip la e als o he
mani old, b) b eakage o he d ip i iga ion
la e al o exhaus ion o hei se ice li e,
and c) high ene gy consump ion.
Se e al au ho s add ess he hyd aulic-
economic op imiza ion o design i iga ion
subuni s. Saad and Ma iño (2002) de eloped
a linea op imiza ion model o ec angula
subuni s, wi h elescopic pipes placed in
he di ec ion o he slope g adien which
minimizes he annualized equi alen
i iga ion and pumping cos s and maximizes
dis ibu ion uni o mi y. Valian zas (2003)
and Valian zas e al. (2007) de i ed a
simple equa ion o calcula e he leng h and
a ailable diame e s o pipes wi hin a subuni
ha minimizes o al annualized pipe and
ene gy cos s. De cas and Valian zas (2012)
p esen ed wo simple analy ical me hods o
calcula e he adequa e diame e s o he main
pipes based on hyd aulic-economic analyzes.
In I icad so wa e (2013), he pipe
sizing is ca ied ou using a Linea
P og amming op imiza ion (LP) in
conjunc ion wi h hyd aulic g ade lines
analysis me hod. Pipe sizes a e op imized
based on he annualized cos o pipes and
ene gy (18). In ake al e posi ion and
p essu e a e de ined by he use wi hou
op imiza ion c i e ia.
 
1/
0
0
x
q
hK
 
 
Ca ión e al. (2013) and Ca ión
e al. (2014) de ised a me hodology
and compu e ool (PRESUD-P esu ized
Submain Design) applied o u bulen
d ippe s o he op imal design o
submains. The c i e ion used o op imize
he design was o educe he o al
annualized cos s o wa e pe i iga ed uni
a ea (CT). They adop ed a double i e a i e
p ocess o he design o he submain
mani old pipe and he in ake al e
p essu e simila o he ones in oduced in
he p esen a icle. Thei app oach is alid
only o ec angula plo s, does no inco -
po a e he elescopic design o submain
mani old pipes and does no iden i y he
op imum in ake al e loca ion.
Mo eno e al. (2016) expands he
PRESUD ool as PRESUD-IR o op imize he
design o iangula o apezoidal plo s. I
inco po a es an ex ension o he algo i hm
abo e men ioned by Ca ión e al. (2013
and 2014); a a hi d i e a ion in ake al e
loca ion is de e mined by conside ing
he loca ion o each emi e as a possible
eeding poin o he submain. The
op imum in ake al e loca ion is he one
ha maximizes dis ibu ion uni o mi y
and minimizes he CT. This upda e does
no inco po a e he elescopic design o
submain mani old pipe and is no sui able
o i egula ly shaped subuni s.
Fo de e mining he op imum in ake
al e loca ion in he submain, p e ious
wo ks (20) s a ed ha he loca ion mus
be aligned o he slope and p essu e loss
in mani old pipes o a single diame e so
as o balance he minimum p essu es
on bo h sides o he al e. Fo elescopic
mani old pipes, his depends on he
selec ed diame e s and leng hs. Finally,
in o de o op imize he eeding poin o
an i iga ion subumain i is necessa y
o imp o e i iga ion uni o mi y and
conside ably educe he cos o pipes.
157
Tomo 51 • N° 2 • 2019
Op imal design o d ip i iga ion submains: P esu e-Compensa ing Emi e s
Rod igo López e al. (1992) said ha
when he a e age slope o he land in he
di ec ion o mani old pipes is less han
3%, i is usually mo e economical o eed
he subuni h ough an in e media e poin
so as o ensu e ha p essu e a ia ion is
almos he same in he mani old pipe o he
ups eam and downs eam eeding poin .
Al hough he e a e some gene al
ecommenda ions and c i e ia o he
op imal design o i iga ion submains
wi h p essu e-compensa ing emi e s,
he e is no me hodology o de ine, bo h
in opog aphies and/o a bi a y geome-
ies, he p essu e and he al e’s in ake
poin and he elescopic sizing o he
submain mani old pipe ha will lead o he
bes possible hyd aulic-economic design.
Objec i e
To de elop a me hodology o subuni s
wi h p essu e-compensa ing emi e s
o op imize: a) elescopic sizing o he
submain mani old pipe; b) he in ake
al e's inpu p essu e o he subuni ; c) he
in ake al e loca ion, by conside ing all
hyd aulic-economic aspec s in ol ed in
he design phase so as o minimize o al
annualized cos s pe i iga ed uni a ea. The
esul ing me hodology is applied wi hin
he design module in d ip i iga ion plo s
in he GESTAR compu e package (2), hus
p o iding a new ad anced unc ionali y.
Ma e ials and Me hods
Fo i iga ion submains wi h p essu e-
compensa ing emi e s, he me hodology
uses as ini ial design condi ion an admis-
sible ange o design p essu es based on
he c i e ia p oposed by Bu and S yles
(2007) and Mon al o (2005). Howe e ,
he use will be able o modi y he
minimum and maximum al e's p essu e
o he design (admissible ange o design
p essu es) acco ding o he cha ac e is ics
and knowledge o he submain.
The Da cy-Weisbach o mula is used
o calcula e p essu e losses in pipes and
la e als whe e: 1) he ic ion ac o ( ) is
de e mined by app oxima ion o he Basius
equa ion (in he case o la e als) and o he
Coleb ook's equa ion o mani old pipes;
and 2) he Ch is iansen educ ion coe i-
cien is used o calcula e p essu e losses in
pipes o la e al acco ding o he numbe o
ou le s as p essu e-compensa ing d ippe s
con o m o his model.
Fo op imal sizing o elescopic
submain mani old pipe, he me hod
de eloped by González and Aliod (2003),
and González (2006) is applied. I is an
op imiza ion algo i hm (LMM/KPH -LM)
ha uses an imp o ed Lag ange Mul i-
plie s Me hod (LMM) (27) in condi-
ions o Know P essu e Head (KPH), in
combina ion o a Labye- ype Me hod
(LM) (22) o s anda diza ion o he
con inous diame e s ob ained in LMM.
A each connec ion poin o e e y la e al
o he submain mani old pipe, he
op imiza ion algo i hm mus supply a
minimum equi ed p essu e so ha he
mos un a o able p essu e-compensa ing
d ippe o he espec i e la e al eaches
i s minimum ope a ing p essu e.
The Nodal Analysis me hod
(1, 9, 10, 11) is used o hyd aulic
simula ion o he i iga ion submain, once
i is al eady designed, which includes a se
o ma ix analysis echniques, ex ended
o conside he speci i ies o p essu e
i iga ion sys ems, ha inco po a es he
in eg al-di e en ial hyd aulic modeling
o d ip la e als whe e he emi e s
discha ge low can depend on he local
p essu e (10, 15, 34). I makes i possible
o pe o m a de ailed quasi-s a iona y
hyd aulic-ene gy simula ion ei he o
u bulen o sel compensa ing d ippe s.
158 Re is a de la Facul ad de Ciencias Ag a ias
C. E. Schila di Sícoli e al.
The baseline da a o be selec ed
includes: a) o he hyd aulic calcula ion o
he subuni , he inne diame e (DI; mm),
leng h (Ll; m), slope (So; m/m), sepa a ion
(dis ance be ween ows; Sl; m) and la e als
pe c op ow (N°la / ow); low (qo; L h-1)
and emi e spacing (Se; m), maximum
(PVmax; m) and minimum design p essu e
(PVmin; m) o he subuni , as well as he
design p essu e s ep ange (PV S ep; m);
b) o he economic calcula ion o he
subuni , g oss c op wa e equi emen s
(Nb; m3 ha-1 yea -1) pe yea , pumping
equipmen e iciency (Ep; %/100), ans-
mission a io (T , his ep esen s he
addi ional amoun o wa e ha mus
be applied du ing he highes demand
pe iod aking in o accoun he ine i able
deep pe cola ion, wi h alues anging
be ween 1.0 and 1.1 (20)), cos o ene gy
(Ce; € kwh-1); wa e p ice (Cw; € m-3); in e es
a e (i; %/100), se ice li e (N); main e-
nance cos as a pe cen age o he i iga ion
sys em pu chase cos (Cm; %/100). Figu e
1 (page 159), shows he low diag am o
he design op imiza ion p ocess.
The p oposed algo i hm i s de e -
mines i he la e al should be ed om
one end o h ough an in e media e
poin by checking i Pmin = minimum
design p essu e o he submain is highe
han Pminobj = minimum a ge design
p essu e. I also e alua es he in e me-
dia e eeding poin o he la e al using
he me hodology de ined by Kelle and
Bliesne (1990) acco ding o he p oce-
du es men ioned in Schila di e al. (2017).
Figu e 1 (page 159), shows a nes ed
i e a ion p ocess o op imally de e mine
he al e p essu e (P op) and op imal
in ake al e loca ion (Nop). The calcu-
la ion sequence begins a he i s possible
in ake poin (N1) wi h an ou e i e a i e
p ocess (posi ion i e a ion), whe e op imal
elescopic sizing o he submain mani old
pipe is ca ied ou a di e en in akes
p essu es which a e s ablished in a second
inne i e a i e p ocess (p essu e i e a ion).
Thus, o each possible in ake posi ion and
o each possible al e p essu e head, om
he minimum (P min) o he maximum
design p essu e (P max) in an inc emen al
ange de ined by he use (PV S ep - Ex:
1 m), he op imal sizing o he submain
mani old pipe is ca ied ou wi h he abo e
men ioned p ocess (LMM-LM/KPH).
A a ian o he LMM me hod o
unknown p essu e head (LMM /UPH)
was no used o ind in a single sequence
pipe sizing and op imal al e p essu e,
a oiding he p essu e i e a ion cycle, since
i depends on he a p io i iden i ica ion o
he mos un a o able poin o he ne wo k,
which is subjec o unce ain y.
As addi ional condi ions o he design
o he i iga ion submain, he speed in
mani old pipes is es ic ed o a ange
o maximum and minimum admissible
alues, which a e de e mined by he use ,
usually be ween 2.5 and 0.5 m s-1.
Fo each p essu e and posi ion i e a ion
( igu e 1, page 159) an op imal design o
he submain mani old pipe is ob ained
and i s annualized o al cos s pe uni o
i iga ed a ea (CT; € ha-1 yea -1), li e-cycle,
o al in es men cos (Ca, € ha-1 yea -1),
main enance cos s (Cm - 5% o Ca; € ha-1
yea -1), ene gy cos s; i pumping is equi ed
(Ce; € ha-1 yea -1) and wa e cos (Cw; € ha-1
yea -1) associa ed o he subuni a e calcu-
la ed as shown in he ollowing equa ion
(Ca ión e al. 2013) which s a es:
(3)
(4)
1.05
a e w
CT C C C  
CT P
9.81
(1 ) (1 ) 3600
(1 ) 1 (1 ) 1
1.05
N N OS O n c
N N OS n w
Q H R
i i i i En
Ep Q eA R T
i i i i
S S S EU
 
−−
   

159
Tomo 51 • N° 2 • 2019
Op imal design o d ip i iga ion submains: P esu e-Compensa ing Emi e s
whe e:
Ci = o al in es men cos (€)
S = i iga ed a ea (ha)
i = in e es a e
N = se ice li e (yea s)
Qos= design low (m3 s-1)
Ho = subuni in ake p essu e (m)
Ep = pumping e iciency (0.65 on a e age)
Rn = annual ne c op wa e equi emen
(m3 ha-1 yea -1)
Enc = a e age cos o ene gy consumed,
(€ kwh-1)
Ea = gene al applica ion e iciency o he
i iga ion sys em (%/100)
T = ansmission a io o maximum
demand pe iod (20)
Pw = p ice o wa e , excluding ene gy
cos s o p essu e supply (€ m-3).
Figu e 1. Subuni op imiza ion p ocess wi h p essu e-compensa ing emi e s (GESTAR).
Figu a 1. Diag ama de lujo del p oceso de op imización de sec o es con emiso es
au ocompensan es (GESTAR).
160 Re is a de la Facul ad de Ciencias Ag a ias
C. E. Schila di Sícoli e al.
Though in he case o p essu e-
compensa ing emi e s he alues o
Cw and Cm a e cons an , hey a e inco -
po a ed in o he calcula ion p ocess o
be compa ed wi h designs made wi h
o he so wa e and/o wi h designs ha
include u bulen emi e s. The a o e-
men ioned cos app oach does no
conside explici elly he ex ended leng h
o he main pipe necessa y o conec he
op imum in ake poin o plo ne wo k.
Ne e heless, his cos and all s o age
and in as uc u e ine es men s equi ed
o make he subuni ope a ional can be
included in Cw and, i i is app op ia e,
also he ene gy cos s asocia ed o head
losses in he plo ne wo k and collec i e
ne wo k ha d i e wa e o he subuni .
Once he double nes ed i e a i e
p ocess is comple ed, he op imal join
design ( elescopic sizing o he submain
mani old pipe, p essu e and al e in ake
loca ion) is de e mined as he al e na i e
ha minimizes he o al annualized cos
pe uni o i iga ed a ea. A soon as he
op imal design has been comple ed, i s
hyd aulic simula ion can be pe o med
o p edic he de ailed p essu e dis i-
bu ion and e i y he p ope hyd aulic
ope a ion o he submain. The desc ibed
me hodology was implemen ed wi hin
he d ip i iga ion design module, in
he GESTAR so wa e package, using he
Visual Basic 6.0 p og amming language,
p o iding a new ad anced unc ionali y.
Resul s
The me hodology is applied o h ee
examples o i iga ion submains wi h
p essu e-compensa ing emi e s o hei
op imal design, whe e he geome ical and
opog aphic con igu a ion is he e oge-
neous. The esul s ob ained a e compa ed
wi h p e ious designs de eloped wi h
ano he comme cial compu e ool
(I icad P o) as a easibili y es .
The submains i iga e ineya ds
ha sha e he ollowing cha ac e is ics:
a) dis ance be ween ows: 2 m, b) dis ance
be ween plan s: 1 m, c) emi e low: 1.60 L h-1,
d) emi e spacing: 0.60 m, e) emi e ange o
compensa ion: 4-40 m, ) ex e nal diame e s
o he la e al: 16 mm, g) in e nal diame e o
he la e al: 15.5 mm, h) numbe o la e als
pe ow: 1 la e al, i) emi e manu ac u ing
a ia ion coe icien : 4%. Fo each example,
he layou o he main pipe uns pa allel o
e e y mani old pipe; his gi es he possibili y
o connec ing he al e a any poin along he
submain mani old pipes.
Based on he ex e nal diame e s (mm),
able 1 shows he cos s pe linea me e
o he possible pipes ha a e used in he
LMM/KPH-LM algo i hm o he submain
mani old pipe op imiza ion.
Fo he hyd aulic-economic op imiza ion
o he submains, he ollowing a iables
ha e been conside ed: a) ene gy p ice:
0.06 € kwh-1, b) wa e p ice: 0.10 € m-3,
c) cos o he la e al: 0.33 € m-1, d) in e es
a e: 7%, e) se ice li e: 25 yea s, ) pump
e iciency: 65%, g) annual ne i iga ion
equi emen s: 6,000 m3 ha-1, h) ansmission
a io: 1.05, and i) main enance cos : 5% o
annualized ma e ial acquisi ion cos (Ca).
Table 1. Ex e nal diame e s o pipes and hei co esponding cos pe linea me e .
Tabla 1. Diáme os ex e nos de ube ías y su co espondien e cos o po me o lineal.
DE (mm) 50 63 75 90 110 125 140 160 200
€/m 1.33 1.39 2.62 2.71 3.12 3.89 4.97 3.36 10.4
161
Tomo 51 • N° 2 • 2019
Op imal design o d ip i iga ion submains: P esu e-Compensa ing Emi e s
Figu e 2 and able 2 show he geome -
ical and opog aphic cha ac e is ics and
he esul s o he p e ious hyd aulic design
o he h ee submains, whe e he al e’s
p essu e (P ), submain low, leng h,
diame e and o al cos o seconda y pipes
a e shown.
Figu e 3 (page 162), shows he new
o m c ea ed wi h he GESTAR ool o
in oduce he necessa y da a o he
op imal hyd aulic-economic design o he
submains. Table 3 (page 162), summa-
izes he esul s o he hyd aulic design
op imiza ion o he submains and shows:
he numbe o hyd aulic designs (Designs
No.), he op imized design al e p essu e
(P ); he leng h, diame e and o al cos o
he mani olds op imized pipes.
While he cos o he la e al o each
design al e na i e (ini ial and op imized)
Table 2. Hyd aulic design cha ac e is ics o he i iga ion sec o acco ding o I icad P o.
Tabla 2. Ca ac e ís icas hid áulicas de diseño de los sec o es de iego ejemplo según
I icad P o.
Ej. S Flow P Diame e (mm) and
leng h (m) o pipes
To al
leng h
To al
Cos
ha m3h-1 m 90 75 63 50 m €
1 2.30 30.67 28 66 56 78 200 354.5
2 1.94 25.87 24 49 70 38 157 369.8
3 2.09 27.87 24 50 65 118 232 376.6
is he same, signi ican cos sa ings a e
achie ed by placing he al e a an in e -
media e poin o he submain mani old
pipe whe e he lows a e di ided and
design is op imized using he p oposed
algo ihm LMM/KPH-LM (13). Thus,
in Example 1 a 22% mani old pipe cos
educ ion is achie ed, while in Example
2 cos educ ion is in he o de o 34%
(because he pipe h oughou i s en i e
leng h is on an ascending slope) and in
Example 3 i is 16%.
Table 4 (page 162), summa izes he main
esul s o he hyd aulic-economic op imi-
za ion o he i iga ion submains and shows:
he in ake poin o he subuni (X/Lp), whe e
X is he dis ance downs eam o he submain
mani old pipe wi h espec o he connec ion
o he al e and Lp is he o al leng h o he
submain mani old pipe (20).
Figu e 2. Geome ic and opog aphic o m o submains (con ou lines e e y 1 m).
Figu a 2. Fo ma geomé ica y opog á ica de sec o es de iego (cu as de ni el cada 1 m).
162 Re is a de la Facul ad de Ciencias Ag a ias
C. E. Schila di Sícoli e al.
Figu e 3. GESTAR o m o da a en y o economic hyd aulic op imiza ion o submains
wi h p essu e-compensa ing emi e s.
Figu a 3. Fo mula io GESTAR de ing eso de da os pa a la op imización hid áulica y
económica de sec o es con emiso es au ocompensados.
Table 3. Op imized hyd aulic design ea u es o he i iga ion submains (Ges a ).
Tabla 3. Ca ac e ís icas de diseño hid áulicas op imizadas de los sec o es de iego (Ges a ).
Table 4. Main hyd aulic ope a ion cha ac e is ics o he op imized Ges a design o
he i iga ion submains (Ges a ).
Tabla 4. P incipales ca ac e ís icas de uncionamien o hid áulico del diseño
op imizado de los sec o es de iego (Ges a ).
Ej. A ea Designs PVop Diame e (mm) and Leng h (m) o pipes To al To al Cos
ha N° m 110 90 75 63 50 m €
1 2.30 1648 15 2 68 122 202 276.2
2 1.94 924 15 2 22.25 43.13 87.51 157 240.9
3 2.09 1648 15 2 72.31 157.59 232 315.4
Ej. X/Lp P (m) Pmax (m) Pmin (m) Vmax (m/s) Vmin (m/s) CeCeOp .
1 77 15 14.46 7.48 2.47 0.041 49.30 23.77
2 72 15 14.90 6.62 2.50 0.102 42.26 26.41
3 92 15 15.24 7.49 2.50 0.041 49.30 26.41