Dimensionally Homogeneous Manning's Formula
Publication: Journal of Hydraulic Engineering
Volume 118, Issue 9
Abstract
Manning was looking for a dimensionally homogeneous velocity equation but did not achieve it. Later the coefficient in one of his equations was related to Kutter's n. The dimension of n is reviewed here. If n is indeed a boundary roughness geometry measure, its dimension should be length to the one-sixth power. Subsequently, a new coefficient ng = (✓g/Kn) n is defined such that an improved, dimensionally homogeneous Manning formula is introduced. A short table of values of ng is provided. Finally, an equation to evaluate the error in using Manning's formula for fully-developed turbulent, steady, uniform flow in rigid boundaries is given.
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References
1.
Barnes, H. H., Jr. (1967). “Roughness characteristics of natural channels.” Water‐Supply Paper 1849. U.S.Geological Survey, Washington, D.C.
2.
Bovey, H. T. (1901). Treatise on hydraulics. 2nd Ed. John Wiley and Sons, New York, N.Y.
3.
Chow, V. T. (1959). Open‐channel hydraulics. McGraw‐Hill Book Co., New York, N.Y.
4.
Dooge, J. C. I. (1991). “The Manning formula in context.” Channel flow resistance: centennial of Manning's formula, B. C. Yen, ed., Water Resources Publications, Littleton, Colo., 136–185.
5.
Henderson, F. M. (1966). Open channel flow. The Macmillan Co., New York, N.Y.
6.
Keulegan, G. H. (1938). “Laws of turbulent flow in open channels.” J. Nat. Bureau of Standards, 21, 707–741.
7.
King, H. W. (1918). Handbook of hydraulics. 1st Ed., McGraw‐Hill Book Co., New York, N.Y.
8.
Manning, R. (1889). “On the flow of water in open channels and pipes.” Trans., Institution of Civil Engineers of Ireland, 20, 161–207.
9.
Manning, R. (1895). “On the flow of water in open channels, Supplement.” Trans., Institution of Civil Engineers of Ireland, 24, 179–207.
10.
Rouse, H. (1938). Fluid mechanics for hydraulic engineers. McGraw‐Hill Book Co., New York, N.Y.
11.
Rouse, H. (1946). Elementary mechanics of fluids. John Wiley and Sons, Inc., New York, N.Y.
12.
Strickler, A. (1923). “Beiträge zur Frage der Geschwindigkeitsformel und der Rauhigkeitszahlen für Ströme, Kanäle und Geschlossene Leitungen.” Mitteilungen des Eidgenössischen Amtes für Wasserwirtschaft, 16, Bern, Switzerland.
13.
Yen, B. C. (1991). “Hydraulic resistance in open channels.” Channel flow resistance: centennial of Manning's formula, B. C. Yen, ed., Water Resour. Publications, Littleton, Colo., 1–135.
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Published In
Journal of Hydraulic Engineering
Volume 118 • Issue 9 • September 1992
Pages: 1326 - 1332
Copyright
Copyright © 1992 ASCE.
History
Published online: Sep 1, 1992
Published in print: Sep 1992
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