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Micro Sprinkler Groundnut performance
Micro sprinkler in onion
DRIP FERTIGATION TO ANNUAL MORINGA
Drip irrigation in chillies
Drip irrigation to coconut
Drip irrigation in cotton – modified geometry
Drip irrigation in Typhonium
Sugarcane drip
Surface Irrigation HydraulicsSurface Irrigation Hydraulics
• AdvanceAdvance– Movement of water from the inlet end to Movement of water from the inlet end to
the downstream endthe downstream end– Curve of Time vs. Distance is NOT linear Curve of Time vs. Distance is NOT linear – Rule-of-Thumb: 1/3 of the total advance Rule-of-Thumb: 1/3 of the total advance
time is needed to reach midpoint of the time is needed to reach midpoint of the furrow lengthfurrow length
Surface Irrigation Hydraulics , Surface Irrigation Hydraulics , Cont’dCont’d
• RecessionRecession– Process of water leaving the surface Process of water leaving the surface
(through infiltration and/or runoff) after (through infiltration and/or runoff) after the inflow has been cut offthe inflow has been cut off
– Usually begins to recede at the Usually begins to recede at the upstream endupstream end
– Can also be plotted as Time vs. Distance Can also be plotted as Time vs. Distance – ““Flatter" curve than the Advance CurveFlatter" curve than the Advance Curve
Surface Irrigation Hydraulics, Surface Irrigation Hydraulics, Cont’dCont’d
• InfiltrationInfiltration– Opportunity Time: difference between Opportunity Time: difference between
Recession and Advance curves Recession and Advance curves – Infiltration Depth: a function of the Infiltration Depth: a function of the
opportunity time and the infiltration opportunity time and the infiltration class (rate) of the soilclass (rate) of the soil
Opportunity TimeOpportunity Time
Infiltration vs. Opportunity TimeInfiltration vs. Opportunity Time
Infiltration ProfileInfiltration Profile
UniformityUniformity• Inherent non-uniformity because Inherent non-uniformity because
recession and advance curves are recession and advance curves are not parallel not parallel
• Factors affectingFactors affecting– Inflow rateInflow rate– SlopeSlope– Soil infiltrationSoil infiltration– RoughnessRoughness– Channel shapeChannel shape– Inflow timeInflow time– Length of runLength of run
EfficiencyEfficiency
• Volume balanceVolume balance– VVgg = V = Vzz + V + Vss + V + Vrr
– g g gross gross– z z infiltration infiltration– s s surface storage surface storage– r r runoff runoff
• (or depth basis): d(or depth basis): dgg = d = dzz + d + dss + d + drr
• Part of infiltration may go to deep Part of infiltration may go to deep percolationpercolation
Improving Irrigation EfficiencyImproving Irrigation Efficiency
• Alternate furrow irrigationAlternate furrow irrigation– Increases advance time, but reduces Increases advance time, but reduces
average infiltration depth (twice the width)average infiltration depth (twice the width)
• Cutback irrigationCutback irrigation– Use large inflow rate during advance, and Use large inflow rate during advance, and
then reduce the inflow to match the soil's then reduce the inflow to match the soil's steady-state infiltration ratesteady-state infiltration rate
– Intensive management is requiredIntensive management is required
Improving Irrigation Efficiency Improving Irrigation Efficiency Cont’dCont’d
• Land smoothing and laser gradingLand smoothing and laser grading– Helps to improve uniformityHelps to improve uniformity
• Surge irrigationSurge irrigation– Alternate on-off periods for applying waterAlternate on-off periods for applying water– Achieve higher efficiencies and uniformities Achieve higher efficiencies and uniformities
in some soilsin some soils– Lends itself to semi-automationLends itself to semi-automation
Treatments
SI1 - Surge irrigation with a stream size of 1.5 lps in
100 m long furrowSI2 - Surge irrigation with a stream size of 2.0 lps in
100 m long furrowC1I1 - Continuous irrigation in 100 m long furrows
with a stream size of 1.5 lpsC1I2 - Continuous irrigation in 100 m long furrows
with a stream size of 2.0 lpsC2I1 - Basin irrigation with a stream size of 1.5 lps
C2I2 - Basin irrigation with a stream size of 2.0 lps
SI1 SI2 C1I1 C1I2 C2I1 C2I2
Irrn. Eff. (%)
80 85 70 75 85 90
Total cycle time
Actual ON time
Total cycle time
Actual ON time
Irrn. Time
280 100 190 70 107 75 104 74
Irrn. No.
1 170 60 130 60 105 70 100 70
2 156 56 125 55 98 61 101 70
3 141 50 118 48 94 57 96 72
4 128 48 112 40 85 55 98 72
5 137 50 105 40 95 58 100 74
6 132 50 102 40 93 54 92 70
7 142 50 114 40 89 60 94 74
8 135 50 120 40 91 56 96 66
9 138 50 125 45 92 52 98 72
10 134 50 123 43 90 54 100 70
11 136 50 125 45 89 57 102 72
Actual supply time variation during advance phase between irrigations ( minutes )
FIG 3 WETTING FRONT ADVANCE PATTERN DURING THE
FIRST IRRIGATION
0
20
40
60
80
100
120
0 20 40 60 80 100 120 140 160
TIME, min
FUR
RO
W L
ENG
TH, m
SI1 SI2 CI1 CI2
FIG.4 WETTING FRONT ADVANCE PATTERN DURING LAST
IRRIGATION
0
20
40
60
80
100
120
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140
TIME, min
FU
RR
OW
LE
NG
TH
, m
SI1 SI2 CI1 CI2
FIG.5. TOTAL ADVANCE TIME FOR EACH IRRIGATION
0
20
40
60
80
100
1 2 3 4 5 6 7 8 9 10 11 12 13
IRRIGATION NUMBER
TIME,
min
SI1 CI1 SI2 CI2
FIG.6. ACTUAL ON TIME DURING EACH IRRIGATION
0
10
20
30
40
50
60
70
80
1 2 3 4 5 6 7 8 9 10 1 12 13
IRRIGATION NUMBER
TIM
E, m
in
SI1 SI2 CI1 CI2