Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-20T10:16:01.007Z Has data issue: false hasContentIssue false

Calculation of flow and pollutant dispersion in meandering channels

Published online by Cambridge University Press:  21 April 2006

A. O. Demuren
Affiliation:
Institute for Hydromechanics, University of Karlsruhe, Karlsruhe, F.R. Germany Present address: Engineering Analysis Unit, University of Lagos, Lagos, Nigeria
W. Rodi
Affiliation:
Institute for Hydromechanics, University of Karlsruhe, Karlsruhe, F.R. Germany

Abstract

Experiments on and calculation methods for flow and pollutant spreading in meandering channels are reviewed. The shortcomings of existing calculation methods are discussed in the light of the complex three-dimensional nature of the flow situation. A mathematical model is presented which takes full account of the three-dimensionality of the flow and pollutant concentration fields. This model is based on the solution of the momentum equations governing the flow in the lateral, vertical and longitudinal directions with a three-dimensional numerical procedure together with the continuity equation. The turbulent stresses appearing in the momentum equations are calculated with a version of the k-ε turbulence model that accounts for streamline curvature effects on turbulence. The pollutant concentration field is subsequently obtained from a solution to its transport equation. The model is tested by application to three different meander situations for which velocity and concentration measurements are available from the literature, with channel width-to-depth ratios in the range 4–20, smooth and rough beds and various pollutant-discharge locations. Detailed comparisons of the velocity and concentration fields show generally good agreement. The effect of streamline curvature on the turbulent mass fluxes was found to be important only in the narrow channel with a smooth bed. Bed-generated turbulence appears to overrule this in the other two cases of a wide channel with a smooth bed and a narrow channel with a rough bed. The flow patterns show the presence of a single large eddy at most cross-sections in these cases, whereas the predictions indicate the presence of usually more than one eddy in the former case.

Type
Research Article
Copyright
© 1991 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ananyan A. K.1957 Dvizhenie zhidkosti na povorote vodovoda. Erevan: Izd. Akad. Nauk. Arm. SSR. [Transl. 1965 Fluid Flow in Bends of Conduits. Jerusalem: Israel Program Sci. Transl.]Google Scholar
Boussinesq J.1868 Mémoire sur l'influence des frottements dans les mouvements reguliers des fluides J. Math. Pures Appl. (2me sér.) 13, 377424.Google Scholar
Bradshaw P.1973 Effects of streamline curvature on turbulent flow. AGARDograph 169.Google Scholar
Callander R. A.1969 Instability and river channels. J. Fluid Mech. 36, 465480.Google Scholar
Callander R. A.1978 River meandering. Ann. Rev. Fluid Mech. 10, 129158.Google Scholar
Chang Y. C.1971 Lateral mixing in meandering channels. Ph.D. thesis, University of Iowa, USA.
Demuren A. O.1983 Three-dimensional numerical computation of flow and pollutant dispersion in meandering channels. Proc. 20th Congress of the IAHR, Moscow, USSR, Vol. III, pp. 2936.
De Vriend H. J.1973 Theory of viscous flow in wide curved open channels. Proc. IAHR Intl. Symp. on River Mechanics, Bangkok, Thailand.
De Vriend H. J.1979 Flow measurements in a curved rectangular channel. Delft University of Technology, Dept. of Civil Engng, Laboratory of Fluid Mechanics, Internal Rep. 979.Google Scholar
De Vriend H. J.1981a Velocity redistribution in curved rectangular channels. J. Fluid Mech. 107, 423439.Google Scholar
De Vriend H. J.1981b Steady flow in shallow channel bends. Comm. on Hydraulics, Delft University of Technology, Rep. No. 813.Google Scholar
De Vriend H. J.1981c Steady flow in shallow channel bends. Doctoral dissertation, Delft University of Technology.
Einstein, H. A. & Harder J. A.1954 Velocity distribution and boundary layer at channel bends. Trans. Am. Geophys. Union 35, 114120.Google Scholar
Elder J. W.1959 The dispersion of marked fluid in turbulent shear flow. J. Fluid Mech. 5, 544560.Google Scholar
Engelund F.1974 Flow and bed topography in channel bends. J. Hydraul. Div. ASCE 100 (HY11), 16311648.Google Scholar
Fischer H. B.1969 The effects of bends on dispersion in streams. Wat. Resources Res. 5, 496506.Google Scholar
Fischer H. B., List E. J., Koh R. C. Y., Imberger, J. & Brooks N. H.1979 Mixing in Inland and Coastal Waters. Academic.
Fukuoka S.1971 Longitudinal dispersion in sinous channels. Ph.D. thesis, University of Iowa, USA.
Fukuoka, S. & Sayre W. W.1973 Longitudinal dispersion in sinous channels. J. Hydraul. Div. ASCE 99 (HY1), 195217.Google Scholar
Gibson M. M.1978 An algebraic stress and heat-flux model for turbulent shear flow with streamline curvature. Intl. J. Heat Mass Transfer 21, 16091617.Google Scholar
Gibson, M. M. & Rodi W.1981 A Reynolds stress closure model of turbulence applied to the calculation of a highly-curved mixing layer. J. Fluid Mech. 103, 161182.Google Scholar
Holley, E. R. & Abraham G.1973 Field tests on transverse mixing in rivers. J. Hydraul. Div. ASCE 99 (HY12), 23132331.Google Scholar
Ikeda S.1975 On secondary flow and bed profile in alluvial curved open channels. Proc. 16th Congress of the IAHR, Sao Paulo, Brazil, vol. 2, pp. 105112.
Ippen A. T., Drinker P. A., Jobin, W. R. & Shemdin O. H.1962 Stream dynamics and boundary shear distributions for curved trapezoidal channels. MIT Hydrodynamics Lab. Rep. No. 47.Google Scholar
Launder B. E., Reece, G. J. & Rodi W.1975 Progress in the development of a Reynolds stress turbulence closure, J. Fluid Mech. 86, 737566.Google Scholar
Launder, B. E. & Spalding D. B.1974 The numerical computation of turbulent flow. Comp. Meth. Appl. Mech. & Engng 3, 269289.Google Scholar
Leonard B. P.1979 A stable and accurate convective modelling procedure based on quadratic upstream interpolation. Comp. Meth. Appl. Mech. & Engng 19, 5998.Google Scholar
Leopold, L. B. & Wolman M. G.1957 River channel patterns: braided, meandering and straight US Geol. Surv. Prof. Paper 282-B, pp. 3786.Google Scholar
Leschziner, M. A. & Rodi W.1979 Calculation of strongly curved open channel flow. J. Hydraul. Div. ASCE 105 (HY10), 12971314.Google Scholar
Leschziner, M. A. & Rodi W.1981 Calculation of annular and twin parallel jets using various discretisation schemes and turbulence-model variations. Trans. ASME: J. Fluids Engng 103, 352360.Google Scholar
Mcguirk, J. & Rodi W.1977 A mathematical model for a vertical jet discharging into a shallow lake. Proc. 17th Congress of the IAHR, Baden Baden, F.R. Germany..
Meckel H.1978 Spiralströmung und Sedimentbewegung in Flu- und Kanalkrümmungen Wasserwirtschaft 68, 287294.Google Scholar
Meckel, H. & Chun V. H.1975 Einflu der Sohlausbildung auf die Strömungsverhältnisse, in Gerinnebögen. In Leitmotiv Wasser (ed. W. Buck & H. H. Bernhart). Universität Karlsruhe.
Mockmore C. A.1943 Flow around bends in stable channels. Trans. ASCE 109, 593619.Google Scholar
Mosonyi, E. & Götz W.1973 Secondary currents in subsequent model bends. Proc. Intl. Symp. on River Mechanics, IAHR, Bangkok, Thailand.
Mosonyi E., Meckel, H. & Meder G.1975 Etude de développement du courant spiral dans de courbes consecutives d'un canal. Proc. 16th congress of the IAHR, São Paulo, Brazil, vol. 2, pp. 347355.
Patankar, S. V. & Spalding D. B.1972 A calculation procedure for heat, mass and momentum transfer in 3D parabolic flows. Intl. J. Heat Mass Transfer 15, 18781806.Google Scholar
Pavlovic, R. N. & Rodi W.1985 Depth-averaged numerical predictions of velocity and concentration fields in meandering channels. Proc. 21st Congress of the IAHR, Melbourne, Australia, pp. 121125.
Pratap, V. S. & Spalding D. B.1976 Fluid flow and heat transfer in three-dimensional duct flows. Intl. J. Heat Mass Transfer 19, 11831188Google Scholar
Rastogi, A. K. & Rodi W.1978 Predictions of heat and mass transfer in open channels, J. Hydraul. Div. ASCE (HY3), 397420.
Rodi W.1980 Turbulence Models and Their Applications in Hydraulics. Delft: International Association for Hydraulic Research.
Rodi W., Pavlovic, R. & Srivatsa S. K.1981 Prediction of flow and pollutant spreading in rivers. In Transport Models for Inland and Coastal Waters (ed. H. B. Fischer), pp. 63111. Academic.
Rodi, W. & Scheuerer G.1983 Calculation of curved shear layers with two-equation turbulence models, Phys. Fluids 26, 14221436.Google Scholar
Rozovskii I. L.1957 Dvizhenie vody na povorote otkrytogo rusla. Kiev: Izd. Akad. Nauk. Ukr. SSR. [Transl. 1961, Flow of Water in Bends of Open Channels. Jerusalem, Israel Program Sci. Transl.]Google Scholar
Shurky A.1949 Flow around bends in an open flume. Trans. ACSE 115, 751779.Google Scholar
Siebert W.1980 Strömungscharakteristiken in einem Kanal mit 180-Krümmungen. Ph.D. thesis, University of Karlsruhe.
Siebert, W. & Götz W.1975 A study on the deformation of secondary flow in models of rectangular meandering channels. Proc. 16th Congress of the IAHR, São Paulo, Brazil. vol. 2, pp. 142149.
Smith R.1981 Effects of non-uniform currents and depth variations upon steady discharges in shallow water. J. Fluid Mech. 110, 373380.Google Scholar
Smith R.1982 Where to put a steady discharge in a river. J. Fluid Mech. 115, 111.Google Scholar
Smith R.1983 Longitudinal dispersion coefficients for varying channels. J. Fluid Mech. 130, 299314.Google Scholar
Tamai N., Ikeuchi K., Yamazaki, A. & Mohamed A. A.1983 Experimental analysis on the open channel flow in rectangular continuous bends. J. Hydrosci. & Hydraul. Engng 1, 1731.Google Scholar
Taylor G. I.1954 The dispersion of matter in turbulent flow through a pipe Proc. R. Soc. Lond. A 219, 186203.Google Scholar
Thomson J.1876 On the origin of windings of rivers in alluvial plains with remarks on the flow of water round bends in pipes. Proc. R. Soc. Lond. 25, 58.Google Scholar
Yen B. C.1965 Characteristics of subcritical flow in a meandering channel. Inst. of Hydr. Res., University of Iowa, Rep.Google Scholar
Yen C. L.1970 Bed topography effect on flow in a meander. J. Hydraul. Div. ASCE 96 (HY1), 5773.Google Scholar
Yotsukura N., Fischer, H. B. & Sayre W. W.1970 Measurements of mixing characteristics of the Missouri River between Sioux City, Iowa and Plattsmouth, Nebraska. US Geological Survey Water-Supply Paper 1899-G.Google Scholar
Yotsukura, N. & Sayre W. W.1976 Transverse mixing in natural channels. Wat. Resources Res. 12, 695704.Google Scholar