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69th SWCS International Annual Conference July 27-30, 2014 Lombard, IL
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69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Wind and Wave Measurements in Irrigation Reservoirs
Yavuz OzerenNational Center for Computational Hydroscience and Engineering
The University of Mississippi, Oxford, MS
Daniel WrenUSDA‐ARS, National Sedimentation Laboratory, Oxford MS
Michele RebaUSDA‐ARS, Delta Water Management Research Unit, Jonesboro, AR
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Introduction
• The earthen embankments of these reservoirs often experience significant erosion primarily due to wind‐generated waves; therefore, require annual repairs if they are not protected.
• The design of effective embankment protection requires knowledge of the wind‐generated wave characteristics and their relationship to embankment erosion.
• Irrigation reservoirs are commonly used for irrigation water storage in lower Mississippi river floodplain.
• A field measurement station was installed in an irrigation reservoir near Harrisburg, AR, to acquire synchronous measurements of wind and wave properties along with levee erosion data.
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Field Site
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Field Site
• Wave staffs• Wind gauge• Erosion pins• Ground‐based LIDAR
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
0
)( dffSfm ii
omo mH 004.4
Field Measurements
An example time series water surface displacement data (June, 2012, Jonesboro, AR). The vertical axis is vertical water surface displacement.
Five‐hour‐average energy spectrum of the measured waves in July 19, 2012
Wave period, wave height and wind speed histograms for the time period between June 2012 and October 2012.
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Field Measurements
Wave characteristics R26(March 2005)
R26(June 2008)
R27(June 2012)
Wind speed, U10 (m/s) 14 (NE) 13 (SW) 9.5 (S)Fetch length 586 450 470Wave height, Hm0 (m) 0.25 0.23 0.14Peak period, Tp (s) 1.7 1.6 1.4Significant period, Ts (s) 1.7 1.6 1.2Mean period, Tm (s) 1.4 1.4 1.1Significant wave height, Hs (m) 0.23 0.20 0.13Maximum wave height, Hmax (m) 0.38 0.39 0.24RMS wave height, Hrms (m) 0.17 0.12 0.09
The ranges of measured wave parameters compared to field measurements in 2005, 2008 and 2012.
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
44.0
220 0025.0
AA
m
UgF
UgH
28.0
2415.00
AA
p
UgF
UgT
Wave Prediction
Method Hm0 (m) Tp (s) tmin(min)
JONSWAP 0.11 1.1 15.2
Wilson (1965) 0.17 1.3 12.5
SMB, Bretschneider (1970) 0.19 1.7 9.4
Krylow (1976) 0.21 1.6 ‐
Donelan (1980) 0.16 1.4 10.3
Ozeren and Wren (2010) 0.14 1.3 11.8
Comparison of empirical wind wave prediction methods
72.0
2min 087.42
AA UgF
Ugt
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Erosion
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Protection techniques
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Floating Wave Barriers
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Floating Wave Barriers
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Floating Wave Barriers
T = 0.6 s, H = 28 mm, h = 0.466m
2.00 2.24 2.48 2.72 2.96 3.20
x (m)
0.0
0.6
z (m)
t=24.399208 s
2.00 2.24 2.48 2.72 2.96 3.20
x (m)
t=24.598543 s
Laboratory and numerical experiments
Shafer lake (2005‐2009)
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Shape and Orientation
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Shape and Orientation
Internal Levees (U = 10 m/s) Floating wave barriers (U = 10 m/s, Breakwater size = 0.5 m)
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
LMRB
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Irrigation reservoir
(R)
Area – A(m2)
Levee Length (m)
Max. Fetch – Fmax (m)
Max. fetch azimuth (deg.)
Shape factor
17 116,500 1,336 483 ‐35 1.0221 123,525 1,421 516 33 0.9514 125,753 1,404 500 ‐47 1.0120 126,755 1,377 510 49 1.0219 128,328 1,411 510 43 1.017 132,719 1,422 508 ‐49 1.043 138,417 1,585 636 22 0.7827 142,109 1,529 562 26 0.949 151,950 1,931 772 12 0.5811 163,354 1,927 796 72 0.64 164,865 1,626 605 ‐59 0.952 167,344 1,687 666 ‐37 0.848 180,782 1,842 715 22 0.7822 198,299 1,802 662 ‐31 0.9413 206,061 1,737 610 ‐51 1.123 209,621 2,150 660 ‐80 0.8410 234,147 1,871 677 ‐43 1.0518 251,165 2,199 866 19 0.7526 286,009 2,239 851 65 0.8512 300,383 2,244 836 ‐33 0.915 303,328 2,267 840 ‐31 0.915 341,414 2,368 865 ‐58 0.941 351,303 2,413 920 ‐30 0.96 462,435 2,742 1030 ‐44 0.9324 464,613 3,119 1119 19 0.7516 774,962 3,814 1472 47 0.7828 818,208 4,106 1311 ‐81 0.8625 1,264,481 4,561 1690 ‐24 0.93
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
• For a given wind speed, fetch length is the key parameter that controls the size of the waves generated in irrigation reservoirs.
• The orientation of the reservoir relative to the predominant wind direction has a strong influence on embankment erosion in irrigation reservoirs, such that, reducing the fetch length in the prevailing wind direction can significantly reduce embankment erosion.
• Ongoing experimental research and reservoir assessment field studies will provide better information about the relations between the wave size and the erosion retreat rate.
Conclusions
69th SWCS International Annual Conference, 27 - 30 July, 2014, Lombard, ILNational Center for ComputationalHydroscience and Engineering
The University ofMississippi
Acknowledgments Carlos AlonsoUSDA‐ARS National Sedimentation Lab. Oxford, MS (retired)
Denis CarmanWhite River Irrigation District, AR
Keith AdmireUSDA‐NRCS National Water Management Center Little Rock, AR
Mustafa AltinakarNCCHE, The University of Mississippi, Oxford, MS
Paul WorkUSGS, Sacramento, CA
Technical support:Glen GreyJacob FergusonAlan Barger
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