Author(s): Oscar Castro-Orgaz; Juan Vicente Giráldez; Jose Luis Ayuso

Linked Author(s): Juan Vicente Giráldez, José Luis Ayuso Muñoz

Keywords: Gradually varied flow; hydraulics; one-dimensional flow; open channels; spillways

Abstract: The definitions of the critical flow condition in open channel hydraulics, based on the momentum and the energy equations, differ from each other if non-hydrostatic pressure and non-uniform velocity distributions are considered. The concept of minimum energy and minimum momentum yields two distinct critical flow conditions, both in terms of their magnitude and their position. Consequently, for a given discharge, there are two singular points in the water surface profile, derived from the momentum and the energy principles, respectively. Extended momentum and energy equations for non-uniform velocity and non-hydrostatic pressure distributions are presented and the critical flow condition is generalized in relation to those conservation laws.

DOI: https://doi.org/10.1080/00221686.2008.9521930

Year: 2008