Friction Factors for Spatially Varied Flow with Increasing Discharge
Publication: Journal of Hydraulic Engineering
Volume 131, Issue 9
Abstract
This paper describes an experimental investigation of how friction factors change for spatially varied flow in sloping channels receiving lateral inflow. The results are compared with those of Beij in 1934, and it is concluded that uniform flow resistance coefficients are not always appropriate for spatially varied flow. Moreover, the common technique of assuming a constant friction factor over the entire length of the channel has been found to have little theoretical justification. The method of Keulegan in 1952 for calculating friction factors in spatially varied flow gives a better estimate, but does not explicitly take account of the lateral inflow rate or velocity. Beij’s 1934 experimental data, which was used by Keulegan does not show a systematic variation of friction factor with lateral inflow rate for a constant Reynolds number although this may be due to the low flowrates used. The results of the present study indicate that the friction factor increases with lateral inflow rate for a constant Reynolds number in the experiments that included subcritical and supercritical flow conditions. A method for calculating friction factors which allows for lateral inflow is presented as a precursor to the development of a general method of evaluating friction factors for spatially varied flow with increasing discharge.
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References
Beecham, S. C., and Khiadani, M. H. (1996). “Frictional characteristics of spatially varied flow.” Proc. 7th Int. Conf. on Urban Storm Drainage, IAHR/IWA, Hanover, Germany, 67–72.
Beij, K. H. (1934). “Flow in roof gutters.” U.S. Dept. of Commerce, Bureau of Standards: Research Paper RP644, Bureau of Standards J. Res., 12, 193–213.
Chow, V. T. (1959). Open-channel hydraulics, McGraw-Hill, New York.
Clauser, F. (1956). “The turbulent boundary layer.” Adv. Appl. Mech., 4, 1–51.
Graf, W. H., and Song, T. (1995). “Bed shear stress in non-uniform and unsteady open-channel flow.” J. Hydraul. Res., 33(5), 699–704.
Hager, W. H. (1983). “Open channel hydraulics of flows with increasing discharge.” J. Hydraul. Res., 21(3), 177–193.
Henderson, F. M. (1966). Open channel flow, Macmillan, New York.
Iwagaki, H. (1952). “On the law of resistance to turbulent flow in smooth open channels.” Proc. 4th Japanese Nat. Congress for Applied Mechanics, Science Council, Tokyo, 245–250.
Izzard, C. F. (1944). “The surface-profile of overland flow.” Trans., Am. Geophys. Union, 24(6), 959.
Keulegan, G. H. (1952). “Determination of critical depth in spatially variable flow.” Proc., 2nd Midwestern Conf. on Fluid Mechanics, Bulletin 149, Ohio State Univ., Engineering Experiment Station, Columbus, Ohio, 67–80.
Powell, R. W. (1946). “Flow in a channel of definite roughness.” Trans-actions of the ASCE, New York, 531–554.
Rouse, H. (1963). “Critical analysis of open channel resistance.” J. Hydraul. Div., Am. Soc. Civ. Eng., 91(4), 1–26.
Sarma, V. N., and Syamala, P. (1991). “Supercritical flow in smooth open channels.” J. Hydraul. Eng., 117(1), 54–63.
Sassoli, F. (1971). “Canali collettori laterali a forte pendenza.” Energ. Elettr., 36, 26–39.
Song, T., and Graf, W. H. (1994). “Non-uniform open-channel flow over a rough bed.” J. Hydrosci. Hydr. Eng., 12(1), 1–25.
Standard Australia Publications (2003). “Plumbing and drainage—stormwater drainage.” AS3500.3, Sydney Australia.
Tu, H., and Graf, W. H. (1993). “Friction in unsteady open-channel flow over gravel beds.” J. Hydraul. Res., 31(1), 99–110.
Yen, B. C., and Wenzel, H. G. (1970). “Dynamic equations for steady spatially varied flow.” J. Hydraul. Div., Am. Soc. Civ. Eng., 96(3), 801–814.
Yen, B. C., Wenzel, H. G., and Yoon, N. Y. (1972). “Resistance coefficients for steady spatially varied flow.” J. Hydraul. Div., Am. Soc. Civ. Eng., 98(8), 1395–1410.
Yoon, N. Y., and Wenzel, H. G. (1971). “Mechanics of sheet flow under simulated rainfall.” J. Hydraul. Div., Am. Soc. Civ. Eng., 97(9), 1367–1386.
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Information
Published In
Journal of Hydraulic Engineering
Volume 131 • Issue 9 • September 2005
Pages: 792 - 799
Copyright
© 2005 ASCE.
History
Received: Apr 2, 2004
Accepted: Jan 26, 2005
Published online: Sep 1, 2005
Published in print: Sep 2005
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