Analytical Solutions of Energy Equation for Rectangular Channels: Direct Approach
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VIEW THE REPLYPublication: Journal of Irrigation and Drainage Engineering
Volume 143, Issue 1
Abstract
An analytical solution of nondimensional hydraulic energy equation is derived in cosine form for the flow in rectangular open channels considering nonhydrostatic pressure and nonuniform velocity distributions across flow depth and friction and turbulent losses. The new inverted energy equation is a single equation describing all the three roots of the nondimensional hydraulic energy equation. The energy losses due to turbulence and bed shear are also implicitly accounted. Only two roots out of the three roots are practically significant, which denote the two alternate depths and are distinguishable for subcritical and supercritical flow, respectively. These equations yield direct determination of alternate depths in a single step, avoiding an iterative procedure. The use of the new equations is illustrated through worked-out examples. The new single-term analytical inverted equations are computationally simple and useful for academicians, field engineers, and practitioners in directly solving in a single step the problems of energy-equation inversion often encountered when dealing with transitions in a channel section, and flows over a dam-spillway and under a sluice gate, with correction-factors and loss coefficients estimated or known.
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References
Bakhmeteff, B. A., and Matzke, A. E. (1936). “The hydraulic jump in terms of dynamic similarity.” Trans. Am. Soc. Civ. Eng., 101(1), 630–647.
Chanson, H. (2004). The hydraulics of open channel flow: An introduction, 2nd Ed., Elsevier, Amsterdam, Netherlands.
Chow, V. T. (1959). Open-channel hydraulics, McGraw-Hill, New York.
Press, W. H., Teukolsky, S. A., Vetterling, W. T., and Flennery, B. P. (1993). “Quadratic and cubic equations.” Chapter 5.6, Numerical recipes in FORTRAN, 1st Ed., Cambridge University Press, New Delhi, India, 178–180.
Singh, S. K. (2008). “Identifying consolidation coefficient: Linear excess pore-water pressure.” J. Geotech. Geoenviron. Eng., 1205–1209.
Singh, S. K. (2013). “Generalized analytical solution for alternate and sequent depths in rectangular channels: Nonuniform velocity.” J. Irrig. Drain. Eng., 426–431.
Singh, S. K. (2015). “Generalized analytical solutions for alternate and sequent depths in rectangular open channels: Sine form.” J. Irrig. Drain Eng., 04014060.
Valiani, A., and Caleffi, V. (2008). “Depth-energy and depth-force relationships in open channel flows: Analytical findings.” Adv. Water Resour., 31(3), 447–454.
Van Driest, E. R. (1946). “Steady turbulent-flow equations of continuity, momentum, and energy for finite systems.” J. Appl. Mech., Trans. Am. Soc. Mech. Eng., 13(3), A-231–A-238.
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© 2016 American Society of Civil Engineers.
History
Received: Jan 9, 2015
Accepted: Jul 21, 2016
Published online: Sep 22, 2016
Published in print: Jan 1, 2017
Discussion open until: Feb 22, 2017
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