Quasi-Conservative Formulation of the One-Dimensional Saint-Venant–Exner Model
Publication: Journal of Hydraulic Engineering
Volume 134, Issue 10
Abstract
Coupling the Saint-Venant equations with the Exner equation a morphodynamic model is produced, which can be used to describe flow and bed evolution in natural rivers. The system of governing equations is hyperbolic and is expressed in nonconservative form. For this reason, fully primitive formulations of the model are often adopted for the solution, which however are known to incorrectly compute strength and celerity of shock waves (bores). In the present work a quasi-conservative formulation of the differential system is proposed, which aims at reducing these errors to a minimum. The performances of the model are assessed by comparison with primitive formulations applied to some schematic cases and with experimental observations obtained on a physical model of a river reach. Results are satisfactory and overcome predictions based on fully primitive formulations.
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Acknowledgments
This research has been partially supported by the Fondazione Cassa di Risparmio di Verona, Vicenza, Belluno ed Ancona (Project MODITE).
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Published In
Journal of Hydraulic Engineering
Volume 134 • Issue 10 • October 2008
Pages: 1521 - 1526
Copyright
© 2008 ASCE.
History
Received: Aug 2, 2006
Accepted: Dec 23, 2007
Published online: Oct 1, 2008
Published in print: Oct 2008
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