Al Kayed, Mustafa 
ORCID: https://orcid.org/0000-0001-7226-6973
(2024)
Flow Characteristics of Transitions in Open Channels.
PhD thesis, Concordia University.
![[thumbnail of Alkayed_PhD_F2024_PDFA.pdf]](https://spectrum.library.concordia.ca/style/images/fileicons/text.png) |
Text (application/pdf)
23MBAlkayed_PhD_F2024_PDFA.pdf - Accepted Version Restricted to Registered users only until 1 November 2026. Available under License Spectrum Terms of Access. |
Abstract
The characteristics of turbulence in open-channel transitions have important implications for hydraulic engineering. This study considers a warped transition that links a rectangular channel section with a relatively large trapezoidal channel section. The change in cross-sectional shape as well as area causes an adverse pressure gradient. As a result, the primary flow separates from the transition sidewalls, turbulence eddies form, and losses of flow energy occur; these conditions reduce hydraulic efficiency and are highly undesirable. Previous researchers have made great efforts to reduce energy losses and improve hydraulic efficiency but have not addressed the issues adequately. This study aims to explore the effectiveness of introducing a honeycomb with small open cells to the transition in order to improve the flow characteristics. This study took an experimental approach. Three-dimensional instantaneous velocities were measured using an acoustic Doppler velocimeter. An analysis of the measurements produced cross-sectional distributions of the longitudinal flow velocity, secondary flow, turbulence kinetic energy, and Reynolds shear stress. The energy losses were determined, and they were compared between the case of a plain warped transition (without a honeycomb) and the case with a honeycomb. The presence of the honeycomb in the transition improved the flow characteristics, reducing flow separation, energy losses, and turbulence strength. The honeycomb helped increase flow uniformity and decrease the maximum velocity in the transition and farther downstream. A potential benefit of a decreased maximum velocity is a decreased risk of channel erosion. The honeycomb worked to prevent the formation of large turbulent eddies that are known to be energy-bearing while avoiding excessive frictional losses of flow energy because the contact area of the passing fluids with the open cells is small. The mechanism at work is that the small open cells effectively limit the size of the largest possible turbulent eddies while distributing the approach flow evenly across the width of the transition. For practical application, a honeycomb can easily be installed at the entrance of a new or existing transition for beneficial effects. This study has contributed to improving the design of irrigation, drainage, and hydropower channels, all of which typically need a transition.
| Divisions: | Concordia University > Gina Cody School of Engineering and Computer Science > Building, Civil and Environmental Engineering |
|---|---|
| Item Type: | Thesis (PhD) |
| Authors: | Al Kayed, Mustafa |
| Institution: | Concordia University |
| Degree Name: | Ph. D. |
| Program: | Civil Engineering |
| Date: | 13 August 2024 |
| Thesis Supervisor(s): | Li, Sheng Samuel |
| Keywords: | Warped transition; honeycomb; control of turbulence; secondary flow; acoustic Doppler velocimetry measurements; flow separation. |
| ID Code: | 994685 |
| Deposited By: | MUSTAFA AL KAYED |
| Deposited On: | 17 Jun 2025 13:58 |
| Last Modified: | 17 Jun 2025 13:58 |
References:
[1] Abbott, D. E., and Kline, S. J. (1962). “Experimental investigation of subsonic turbulence flow over single and double backward-facing steps.” J. of Basic Engineering 84(3), 317–325.[2] Alauddin, M., and B. C. Basak. (2006) “Development of an expansion transition in open channel subcritical flow.” J. Civ. Eng. 34 (2): 91–101.
[3] Amruthur S. Ramamurthy, Sanjay Basak, Pattabhi Rama Rao (1970) “Open Channel Expansions fitted with Local Hump," Journal of the Hydraulics Division, ASCE, (96, 5), pp. 1105-1113.
[4] Asnaashari, A., A. A. Akhtari, A. A. Dehghani, and H. Bonakdari. (2016) “Experimental and numerical investigation of the flow field in the gradual transition of rectangular to trapezoidal open channels.” Eng. Appl. Comput. Fluid Mech. 10 (1): 272–282.
[5] Austin, Lloyd H.; Skogerboe, Gaylord V.; and Bennett, Ray S. (1970), "Subcritical Flow at Open Channel Structures Open Channel Expansions". Reports. Paper 638.
[6] Basak, B. C., and M. Alauddin. (2010) “Efficiency of an expansive transition in an open channel subcritical flow.” DUET J. 1 (1): 27–32.
[7] Chaturvedi, R. S. (1963). "Expansive subcritical flow in open channel transitions." J. of the Institution of Engineers, Civil Engineering Division, India, 43(May), 447–487.
[8] Chow, V.T. (1959) "Open-Channel Hydraulics," McGraw-Hill Book Co., New York.
[9] Cruise, J.F., Sherif M.M, and Singh V.P. (2007) “Elementary Hydraulics” Thomson Nelson, Canada.
[10] El-Shewey, M. I. A., and Joshi, S. G. (1996). "A study of turbulence characteristics in open channel transitions as a function of Froude and Reynolds numbers using laser technique." Advanced Fluid Mechanics, 9, 363–372.
[11] Feil, O.G. (1962). "Vane system for very wide-angle sub-sonic diffusers." Report PD 7, Department of Mechanical Eng. Stanford University.
[12] Formica, G. (1955) “Esperienze preliminary sulle predate di carcico nei caneli, dovute a combiamenti di sezione [Preliminary tests on head losses in channels due to cross sectional changes]”, L'Energia Electrica, Milano, Vol. 32, No. 7, pp. 554-568, July (in Italy).
[13] Foumeny, E. A, Ingham, D. B, and Walker, A. J. (1996). “Bifurcations of incompressible flow through plane-symmetric channel expansions.” Journal of Computers and Fluids 25(3), 335–351.
[14] Frizzel, C., and Werth, D. (2006). “Flow separation downstream of equal and opposing flow junctions in open channels.” Proceedings of the World Environmental and Water Resources Congress Omaha, Nebraska, USA.
[15] Garde, R. J., Ranga Raju, K. G., and Misra, R. C. (1979) “Subcritical flow in an open channel Expansions” The Journal of the Central Board of Irrigation and Power. Vol. 36, Issue No. 1:45-54.
[16] Graber, S. D. (1982). “Asymmetric flow in symmetric expansions.” J. of the Hydraulics Division, ASCE 108(HY10): 1082–1101.
[17] Graber, S. D. (2006). “Asymmetric flow in symmetric supercritical expansions” J. of Hydraulics Engineering, ASCE 132 Issue 2: 207-213.
[18] Haque, A. (2008) “Some characteristics of open channel transition flow.” M.A.Sc. thesis, Dept. of Building, Civil and Environmental Engineering, Concordia University.
[19] Han, Sang Soo (2010) “Use of vanes in sharp bends to improve open-channel flow characteristics: Laboratory and numerical experiments” Ph.D. Thesis, Dept. of Building, Civil and Environmental Engineering, Concordia University.
[20] Henderson, F. M. (1966) Open channel flow. Upper Saddle River, NJ: Prentice-Hall.
[21] Hinds, J. (1928) “Hydraulic Design of Flume and Siphon Transitions,” ASCE, Paper No. 1690, Volume / Issue 92 (1), pp 1423 – 1459.
[22] Hinze, J. O. (1975). "Turbulence". 2nd Edition, McGraw-Hill Book Co., New York. 638-650.
[23] Hix, Kyle David (2020). “Experimental evaluation of a honeycomb structure in open channel flows.” Master’s thesis of science in civil engineering, Missouri University of Science and Technology, Missouri, USA.
[24] Ippen, A. T. (1949) “Channel Transitions and Controls.” Proceedings of 4th Hydraulics Conference, Iowa Institute of Hydraulic Research, Engineering Hydraulics, June 1949. John Wiley & Sons, inc. pp 496-588.
[25] Isbash, S. V., and Lebedev, I. V. (1961). "Change of natural streams during construction of hydraulic structures." Proceedings, 9th Congress of IAHR, Dubrovnik, Yugoslavia, 1114-1121.
[26] Kalinske, A. A. (1946). "Conversion of kinetic energy to potential energy in flow expansions."ASCE, Vol. Ill, 355-390.
[27] Knight, Donald W., Demetriou, John D., and Hamed, Mohammed E. (1984). “Boundary shear in smooth rectangular channels” Journal of Hydraulic Engineering, ASCE 110 (4): 405-422.
[28] Li S.S., Thapa D. R., Ramamurthy A.S. (2019) “Using vanes to reduce flow separation and head loss in wrapped transition.” J. Irrig. Drain Eng. 145 (2): 04018042.
[29] Li, S.S. (2022) "Harmonic function for 3D warped transition geometry and its practical use." Journal of Irrigation and Drainage Engineering, ASCE 148(6): 06022002. DOI: 10.1061/(ASCE)IR.1943-4774.0001679
[30] MacVicar, B.J.; Roy, A.G. (2011) “Sediment mobility in a forced riffle-pool.” Geomorphology, 125, 445–456.
[31] Manal Gad; Hany Abd-Elhamid; Martina Zeleňáková; Hanaa Salem Marie; Wael O. Nassar. “Developing improved machine learning methods to predict the flow characteristics through vertical and horizontal transitions in open channels.” Journal of Hydroinformatics (2024) 26 (7): 1534–1557. https://doi.org/10.2166/hydro.2024.262
[32] Monsif Shinneeb, Ghassan Nasif, Ram Balachandar (2021). “Computational investigation of the effect of the aspect ratio on secondary currents in open channels”, WIT Transactions on Engineering Sciences, Volume 132, Pages 11, Page Range 49 – 59, Paper DOI 10.2495/MPF210051.
[33] Mazumder, S.K. (1967). “Optimum length of transition in open channel expansive subcritical flow.” J. of IE (I), Vol. XL VIII, No. 3, Pt. CI 2, Nov. 1967.
[34] Mazumder S.K. and Hager W.H., (1993). “Supercritical expansion flow in Rouse modified and reversed transitions.” Journal of Hydraulic Engineering 119(2):201-219.
[35] Mehta, P. R. (1979) “Flow characteristics in two-dimensional expansions.” J. Hydraul. Div. 105 (HY5): 501–516.
[36] Mehta, P. R. (1981) “Separated flow through large sudden expansions.” J. Hydraul. Div. 107 (HY4): 451–460.
[37] Mitra, A. C. (1940). "Report on the model experiments of flaming of bridges on Purva branch." Technical Memorandum. 9, United Provinces Irrigation Res. Inst., Roorkee, India, 94–98.
[38] Morris, H. M., and Wiggert, J. M. (1972). “Applied hydraulics in engineering.” Second edition. The Ronald Press, N.Y.
[39] Najafi-Nejad-Nasser, A., and S. S. Li. (2015) “Reduction of flow separation and energy head losses in expansions using a hump.” J. Irrig. Drain. Eng. 141 (3): 04014057.
[40] Najmeddin, S., and S. S. Li. (2016) “Numerical study of reducing flow separation zone in short open-channel expansions by using a hump.” J. Irrig. Drain. Eng. 142 (7): 06016006.
[41] Nashta, C. F., and Grade, R. J. (1988). “Subcritical flow in rigid-bed open channel expansions.” Journal of Hydraulic Research 26(1), 49–65.
[42] Nikora, V.I., and D.G. Goring (2002) .” Turbulence structure in a gravel-bed flow with weak bed-load”. Draft manuscript submitted to Journal of Geophysical Research.
[43] Papanicolaou, A., and Hilldale, R. (2002). "Turbulence characteristics in a gradual channel transition." J. of Engineering Mechanics 128(9), 948–960.
[44] Quteishat, Mustafa Al Kayed (2020) "Hydrocyclone flow characteristics and measurements" Flow Measurement and Instrumentation, Elsevier.Vol. 73(2020)1017(4). DOI: https://doi.org/10.1016/j.flowmeasinst.2020.101741
[45] Ramamurthy, A.S., Thapa, D.R. & Li, S.S. (2017) "Experimental study of flow past a warped transition." Journal of Irrigation and Drainage Engineering - ASCE 143(8): 04017022. DOI: 10.1061/ (ASCE) IR.1943-4774.0001200.
[46] Rui Zeng and S. Samuel Li (2023). “Large-eddy simulation of free-surface turbulent flow in a non-prismatic channel.” September 2023, Journal of Hydroinformatics 25(1), DOI: 10.2166/hydro.2023.018.
[47] Schwartz, John S. (2016) “Use of Ecohydraulic-Based Mesohabitat Classification and Fish Species Traits for Stream Restoration Design,” Water, www.mdpi.com/journal/water. 8(11): 520, DOI:10.3390/w8110520.
[48] Scobey, F. C. (1933) “The flow of water in flume,” U.S. Department of Agriculture, Technical Bulletin No. 393, December 1933.
[49] Scobey, F. C. (1939) “Flow of water in irrigation and similar canals,” U.S. Department of Agriculture, Technical Bulletin No. 652, February 1939.
[50] Seetharamiah, K., and Ramamurthy, A. S. (1968). "Triangular sills in open channel expansions." Civil Engineering and Public Works Review, Vol. 63, 283.
[51] Skogerboe, G. V., Austin, L. H., and Bennett, R. S. (1971). “Energy loss analysis for open channel expansions.” J. of the Hydraulics Division, ASCE 97(HY10): 1719–1735.
[52] Smith, C. D., and J. N. G. Yu. (1966) “Use of baffles in open channel expansions.” J. Hydraul. Div. 92 (HY2): 1–17.
[53] Schlichting, H. and Gersten, K. 2017. Boundary-layer theory. Springer-Verlag, Berlin Heidelberg.
[54] Siyu Jing, Wenjun Yang, and Yue Chen (2019). “Smooth Open Channel with Increasing Aspect Ratio: Influence on Secondary Flow”, MDPI, Hydraulics and Hydrodynamics, Water 2019, 11(9), 1872; https://doi.org/10.3390/w11091872.
[55] Swamee, P. K., and B. C. Basak. (1991) “Design of rectangular open channel expansion transitions.” J. Irrig. Drain. Eng. 117 (6): 827–838.
[56] Swamee, P. K., and B. C. Basak. (1992) “Design of trapezoidal expansive transitions.” J. Irrig. Drain. Eng. 118 (1): 61–73.
[57] Swamee, P. K., and B. C. Basak. (1993) “Comprehensive open-channel expansion transition design.” J. Irrig. Drain. Eng. 119 (1): 1–17. https://doi.org/10.1061/ (ASCE) 0733-9437(1993) 119:1(1).
[58] Thapa Devi Ram; Li S. Samuel; and Ramamurthy Amruthur S. (2018) “Experimental study of flow characteristics in wedge and modified wedge transitions,” Journal of Hydraulic Engineering, ASCE 144 (8), (ASCE) HE. 040818043.
[59] U.S. Department of Transportation (2006) “Hydraulic design of energy dissipaters for culverts and channels.” Hydraulic Engineering Circular Number 14, Third Edition.
[60] Vectrino-Nortek datasheets lab; http://www.nortek-es.com/lib/data-sheets/datasheet-vectrino-lab.
[61] Vittal, N., and V. V. Chiranjeevi. (1983) “Open channel transitions: Rational method of design.” J. Irrig. Drain. Eng. 109 (1): 99–115.
[62] Wang, X., Yi, Z., Xufeng, Y., Huang, E., and Liu, X. (2015) “Experimental study of the flow structure of decelerating and accelerating flows under a gradually varying flume”. Journal of Hydrodynamics. 27 (3), 340-349.
[63] Warda, Ahmed, Li, Samual, Ramamurthy, Amruthur (2018) “Investigation of discharge coefficient for siphon spillway”, conference CSCE Building Tomorrow’s Society, June 13 – June 16, 2018, Fredericton, Canada.
[64] Wilcox, David C. (2006); Turbulence Modeling for CFD, 3rd edition, DCW Industries. ISBN 978-1-928729-08-2 (1-928729-08-8).
[65] WinADV software by Bureau of Reclamation, U.S. Department of the Interior (USBR).
https://www.usbr.gov/tsc/techreferences/computer%20software/software/winadv/index.html.
All items in Spectrum are protected by copyright, with all rights reserved. The use of items is governed by Spectrum's terms of access.
Repository Staff Only: item control page
Download Statistics
Download Statistics