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Finite-amplitude alternate bars

Published online by Cambridge University Press:  21 April 2006

M. Colombini
Affiliation:
Istituto di Idraulica, Facoltà di Ingegneria, Genova, Italy
G. Seminara
Affiliation:
Istituto di Idraulica, Facoltà di Ingegneria, Genova, Italy
M. Tubino
Affiliation:
Istituto di Idraulica, Facoltà di Ingegneria, Genova, Italy

Abstract

Following ideas developed in the field of hydrodynamic stability of laminar flows (Stuart 1971) a predictive theory is proposed to determine the development of finite-amplitude alternate bars in straight channels with erodible bottoms. It is shown that an ‘equilibrium amplitude’ of bedforms is reached as t → ∞ within a wide range of values of the parameter (β − βc)/βc, where t is the time, β is the width ratio of the channel and βc is its ‘critical’ value below which bars would not form. The theory leads to relationships for the maximum height and the maximum scour of bars which compare satisfactorily with the experimental data of various authors. Moreover the experimentally detected tendency of the bed perturbation to form diagonal fronts is qualitatively reproduced.

Type
Research Article
Copyright
© 1987 Cambridge University Press

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References

Ashida, K. & Shiomi, Y. 1966 Study on the hydraulic behaviours of meander in channels. Disaster Prevention Research Institute Annuals, Kyoto Univ., No. 9, pp. 457477.
Blondeaux, P. & Seminara, G. 1985 A unified bar-bend theory of river meanders. J. Fluid Mech. 157, 449470.Google Scholar
Bray, D. I. 1979 Estimating average velocity in gravel bed rivers. Hydraul. Div., ASCE 105 (HY9), 1103–1122.Google Scholar
Callander, R. A. 1969 Instability and river channels. J. Fluid Mech. 36, 465480.Google Scholar
Chang, H., Simons, D. B. & Woolhiser, D. A. 1971 Flume experiments on alternate bar formation. J. Waterways, Harbors, Coastal Engng Div., ASCE 97, 155165.Google Scholar
Chien, N. 1954 The present status of research on sediment transport. J. Hydraul. Div., ASCE 80, 1954.Google Scholar
Einstein, H. A. 1950 The bedload function for sediment transport in open channel flow. US Dept. Agric. Tech. Bull. 1026.Google Scholar
Engelund, F. 1970 Instability of erodible beds. J. Fluid Mech. 42, 225244.Google Scholar
Engelund, F. 1981 The motion of sediment particles on an inclined bed. Tech. Univ. Denmark ISVA Prog. No. 53, pp. 1520.
Engelund, F. & Fredsœ, J. 1982 Sediment ripples and dunes. Ann. Rev. Fluid Mech. 14, 1337.Google Scholar
Engelund, F. & Hansen, E. 1967 A Monograph on Sediment Transport in Alluvial Streams. Copenhagen: Danish Technical Press.
Engelund, F. & Skovgaard, O. 1973 On the origin of meandering and braiding in alluvial streams. J. Fluid Mech. 57, 289302.Google Scholar
Exner, F. M. 1925 Uber die Wechselwirkung zwischen Wasser und Geschiebe in Flussen. Sitzber Akad. Wiss, pp. 165180.
FredsÒ, J. 1978 Meadering and braiding of rivers. J. Fluid Mech. 84, 609624.Google Scholar
FredsÒ, J. 1982 Shape and dimensions of stationary dunes in rivers. J. Hydraul. Div. ASCE 108 (HY8), 932–947.Google Scholar
Hansen, E. 1967 On the formation of meanders as a stability problem. Hydraulic Lab. Tech. Univ. Denmark Basic Res. Prog. Rep., vol. 13, pp. 913.Google Scholar
Hayashi, T. 1970 Formation of dunes and antidunes in open channels. J. Hydraul. Div. ASCE 96 (HY2), 357–366.Google Scholar
Ikeda, S. 1982 Prediction of alternate bar wavelength and height. Rep. Dept. Found. Engng & Const. Engng, Saitama Univ., vol. 12, pp. 2345.
Ikeda, S., Parker, G. & Sawai, K. 1981 Bend theory of river meanders. Part 1. Linear Development. J. Fluid Mech. 112, 363377.Google Scholar
Jaeggi, M. 1983 Alternierende Kiesbänke. Mitteilungen der Versuchsanstalt für Wasserbau, Hydrologie und Glaziologie. Zurich: E.T.H.
Jaeggi, M. 1984 Formation and effects of alternate bars. J. Hydraul. Engng. ASCE 110, 142156.Google Scholar
Kennedy, J. F. 1963 The mechanics of dunes and antidunes in erodible-bed channels. J. Fluid Mech. 16, 521544.Google Scholar
Kinoshita, R. 1961 Investigation of channel deformation in Ishikari River. Rep. Bureau of Resources, Dept. Science & Technology, Japan, pp. 1174.
Kitanidis, P. K. & Kennedy, J. F. 1984 Secondary current and river meander formation. J. Fluid Mech. 144, 217229.Google Scholar
Muramoto, Y. & Fujita, Y. 1978 The classification of meso-scale river bed configuration and the criterion of its formation. Proc. 22nd Japanese Conf. on Hydraulics, pp. 275282. JSCE.
Olesen, K. W. 1983 Alternate bars in and meandering of alluvial rivers. Commun. Hydraul., Rep. 7–83, Delft Univ. of Technology.Google Scholar
Parker, G. 1976 Or the cause and characteristic scales of meandering and braiding in rivers. J. Fluid Mech. 76, 457480.Google Scholar
Parker, G. 1978 Self-formed straight rivers with equilibrium banks and mobile bed. Part 2. The gravel river. J. Fluid Mech. 89, 127147.Google Scholar
Parker, G. 1984 Discussion of: Lateral bed load transport on side slopes. By S. Ikeda. J. Hydraul. Engng, ASCE 110, 197199.Google Scholar
Richards, K. J. 1980 The formation of ripples and dunes on an erodible bed. J. Fluid Mech. 99, 597618.Google Scholar
Shen, H. W. 1962 Development of bed roughness in alluvial channels. J. Hydraul. Div. ASCE 88 (HY3), 45–58.Google Scholar
Stuart, J. T. 1971 Nonlinear stability theory. Ann. Rev. Fluid Mech. 3, 347370.Google Scholar
Sukegawa, N. 1971 Study on meandering of streams in straight channels. Rep. Bureau of Resources, Dept. Science & Technology, Japan, pp. 335363.
Sumer, B. M. & Bakioglu, M. 1984 On the formation of ripples on an erodible bed. J. Fluid Mech. 144, 177190.Google Scholar
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