Momentum Exchange in Straight Uniform Compound Channel Flow
Publication: Journal of Hydraulic Engineering
Volume 131, Issue 3
Abstract
Transverse exchange of momentum between the channel and the floodplain in straight uniform compound channel flow is considered in this paper. This process results in the so-called “kinematic effect,” a lowering of the total discharge capacity of a compound channel compared to the case where the channel and the floodplain are considered separately. The mechanisms responsible for the momentum exchange are considered. The transverse shear stress in the mixing region is modeled using a newly developed effective eddy viscosity concept, that contains: (1) the effects of horizontal coherent structures moving on an uneven bottom, taking compression and stretching of the vortices into account and (2) the effects of the three-dimensional bottom turbulence. The model gives a good prediction of the transverse profiles of the streamwise velocity and the transverse shear stress of the flood channel facility experiments. Characteristic features of the lateral profile of the eddy viscosity are also well predicted qualitatively, but in a quantitative sense there is room for improvement. Secondary circulations are shown to be of minor importance in straight uniform compound channel flows.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
This research is supported by the Technology Foundation STW, Applied Science Division of NWO, and the technology program of the Ministry of Economic Affairs.
References
Alavian, V., and Chu, V. H. (1985). “Turbulent exchange flow in shallow compound channel.” Proc., 21st IAHR Congress, Melbourne, Australia, 446–451.
Barishnikov, N. B., and Ivanov, G. V. (1971). “Role of flood plain in flood discharge of a river channel.” Proc., 14th IAHR Congress, Paris, 141–144.
Cramp, A., Coulson, M., James, A., and Berry, J. (1991). “A note on the observed and predicted flow patterns around islands—Flat Holm, the Bristol Channel.” Int. J. Remote Sens., 12(5), 1111–1118.
Dracos, T., Giger, M., and Jirka, G. H. (1992). “Plane turbulent jets in a bounded fluid layer.” J. Fluid Mech., 214, 587–614.
Ervine, D. A., Babaeyan-Koopaei, K., and Sellin, R. H. J. (2000). “Two-dimensional solution for straight and meandering overbank flows.” J. Hydraul. Eng., 126(9), 653–669.
Fischer, H. B., List, E. J., Koh, R. C. J., Imberger, J., and Brooks, N. H. (1979). Mixing in inland and coastal waters, Academic, New York.
Ikeda, S., Kawamura, K., Toda, Y., and Kasuya, I. (2002). “Quasi-three-dimensional computation and laboratory tests on flow in curved compound channels.” Proc., Riverflow 2002, Louvain-la-Neuve, Belgium, 233–245.
Knight, D. W., and Shiono, K. (1990). “Turbulence measurements in a shear layer region of a compound channel.” J. Hydraul. Res., 28(2), 175–196.
Lambert, M. F., and Sellin, R. H. J. (1996). “Discharge prediction in straight compound channels using the mixing length concept.” J. Hydraul. Res., 34(3), 381–394.
Nadaoka, K., and Yagi, H. (1998). “Shallow-water turbulence modeling and horizontal large-eddy computation of river flow.” J. Hydraul. Eng., 124(5), 493–500.
Ogink, H. J. M. (1985). “The effective viscosity coefficient in 2-D depth-averaged flow models,” Proc., 21st IAHR Congress, Melbourne, Australia, 475–479.
Pope, S. B. (2000). Turbulent flows, Cambridge University Press, Cambridge, U.K.
Sellin, R. H. J. (1964). “A laboratory investigation into the interaction between the flow in the channel of a river and that over its flood plain.” Houille Blanche, 110, 689–789.
Shiono, K., and Knight, D. W. (1991). “Turbulent open channel flows with variable depth across the channel.” J. Fluid Mech., 222, 617–646.
Sofialidis, D., and Prinos, P. (1998). “Compound open-channel flow modeling with nonlinear low-Reynolds models.” J. Hydraul. Eng., 124(3), 253–262.
Sofialidis, D., and Prinos, P. (1999). “Numerical study of momentum exchange in compound open channel flow.” J. Hydraul. Eng., 125(2), 152–165.
Tamai, N., Aseada, T., and Ikeda, H. (1986). “Study on generation of periodical large surface eddies in a composite channel flow.” Water Resour. Res., 22(7), 1129–1138.
Tennekes, H., and Lumley, J. L. (1972). A first course in turbulence, MIT Press, Cambridge, Mass.
Tominaga, A., and Nezu, I. (1991). “Turbulent structure in compound open-channel flows.” J. Hydraul. Eng., 117(1), 21–41.
Uijttewaal, W. S. J., and Booij, R. (2000). “Effects of shallowness on the development of free-surface mixing layers.” Phys. Fluids, 12(2), 392–420.
Van Prooijen, B. C., and Uijttewaal, W. S. J. (2002). “A linear approach for the evolution of coherent structures in shallow mixing layers.” Phys. Fluids, 14(12), 4105–4114.
Vreugdenhil, C. B. (1994). Numerical methods for shallow-water flow, Kluwer Academic, Dordrecht, The Netherlands.
Wormleaton, P. R. (1988). “Determination of discharge in compound channels using the dynamic equation for lateral velocity distribution.” Proc., Int. Conf. on Fluvial Hydraulics, IAHR, Budapest, Hungary, 98–103.
Wormleaton, P. R. (1996). “Coherent flow structures in open channels.” Floodplain secondary circulation as a mechanism for flow and shear stress redistribution in straight compound channels, P. J. Ashworth, S. J. Bennet, J. L. Best, and S. J. McLelland, eds., Wiley, Chichester, England, 581–608.
Information & Authors
Information
Published In
Copyright
© 2005 ASCE.
History
Received: Mar 11, 2003
Accepted: Sep 29, 2004
Published online: Mar 1, 2005
Published in print: Mar 2005
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.