Home / The library / Geophysical Hydraulics / Fluvial hydraulics / Normal flow and uniform equilibrium flow conditions in open channels

Normal flow and uniform equilibrium flow conditions in open channels

In open channels, the water flow is driven by gravity. In a long inclined prismatic channel, the flow will reach normal flow when there is an exact equilibrium between the gravity force component in the streamwise direction and the shear force. The water depth and velocity become independent of time and position at uniform equilibrium.
The momentum equation along a streamline states the exact balance between the shear forces and the gravity component. The normal flow conditions (i.e. uniform equilibrium flow properties) are deduced from the continuity and momentum equations. The calculations may require several iterations, depending upon the initial selection of a water depth. For turbulent flows, the Darcy-Weisbach factor may be estimated using the Colebrook-White formula or graphically from the Moody diagram.
Hubert Chanson.

Additional notes
YouTube channel >>
Hubert Chanson
Hubert Chanson
HENDERSON, F.M. (1966). "Open Channel Flow." MacMillan Company, New York, USA.
CHANSON, H. (2004). "The Hydraulics of Open Channel Flow: An Introduction." Butterworth-Heinemann, 2nd edition, Oxford, UK, 630 pages (ISBN 978 0 7506 5978 9).

IAHR Media Library

This web site was launched by Prof. Michele Mossa of the Polytechnic University of Bari (Italy) with the initial support of Fondazione Caripuglia, Bari, Italy for the Research Project LIC-MON of 2003 and of the Project IMCA (Integrated Monitoring of Coastal Areas) financed by MIUR PON D.M. 593/00. Later, the initiative was supported with other Prof. Michele Mossa’s funds, most recently provided by the RITMARE Project.

IAHR Media Library
Advertise with us

for more information please contact us: info@iahrmedialibrary.net

© IAHR Media Library
Alticom - studio