Volume 13, Numéro 4, Pages 25-38

Flow Predictions In Vegetated Open Channels

Authors : Morri M . Soualmia A . Belleudy P .


Vegetation development in river bed and in the banks, may affect the hydraulic conditions and hydrodynamic behavior of a stream. Understanding flow dynamic within vegetation becomes very important to control floods and the stream ecosystem. The present paper explores the capacity of a model in a twodimensional code Telemac2D, to predict flow characteristics in vegetated open channel. This model adopted a two-layer approach to determine the mean velocity in vegetated flume using vegetation characteristics. The verification of the programmed model capacity was based on comparison between simulations and measured results derived from the experiences of Keramaris Evangelos (2012), Sergio De Felice (2008) and Le Bouteiller and Venditti (2014). These experiments were conducted with submerged vegetation in a rectangular open channel flow to determine the vegetation effects on flow processes. The comparison shows a good agreement between the simulations results and the measured ones in presence of slopes. This programmed model was more accurate in the case of rigid vegetation than flexible vegetation. In general, the new roughness model could be used to predict the effect of vegetation resistance on flow, which is a very important phenomenon to control river floods.


Vegetation, hydraulic, floods, two-dimensional code, open channel