Topographic forcing of flow partition and flow structures at river bifurcations

Auteur(s) et Affiliation(s)

MIORI, S.

Dip. di Ingegneria Civile e Ambientale, Univ., Trento, Italie

HARDY, R.J.

Dep. of Geography, Univ., Durham, Royaume-Uni

LANE, S.N.

Inst. de Géographie, Fac. des Géosciences et de l'Environnement, Univ., Lausanne, Suisse

Description :
The aim of this paper is to explore the interaction between bedform steered flow and bifurcation dynamics. The AA. present the predicted flow dynamics from the application of a Reynolds-averaged Navier–Stokes (RANS) model to a series of bifurcation geometries with morphologies measured during previous flume experiments. The topography of the bifurcations consists of either plane or bedform-dominated beds which may or may not possess discordance between the 2 bifurcation distributaries. The results demonstrate the dominant effect bed discordance has upon flow division between the 2 distributaries. They also suggest that sand-bed river bifurcations are more likely to have an influence that extends much further upstream and have a greater impact upon water distribution. This may contribute to observed morphological differences between sand-bedded and gravel-bedded braided river networks.

Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2012, vol. 37, n°. 6, p. 666-679, nombre de pages : 14, Références bibliographiques : 61 ref.

Date :
2012

Editeur :
Pays édition : Royaume-Uni, Chichester, Wiley

Langue :
Anglais