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(Article of periodic en Anglais - 2013)

Document title

Macroturbulent coherent structures in an ice-covered river flow using a pulse-coherent acoustic Doppler profiler

Authors(s) and Affiliation(s)

DEMERS S. (1) ; BUFFIN-BÉLANGER T. (1) ; ROY A.G. (2) ;
(1) Dept. de biologie, chimie et géographie, Univ. du Québec, Rimouski, CANADA
(2) Dept. de Géographie, Université de Montréal, Montréal, CANADA

Abstract

The AA. compare macroturbulent coherent structures (MCS) geometry and organization between ice covered and open channel flow conditions. Velocity profiles were obtained using a Pulse-Coherent Acoustic Doppler Profiler in both open channel and ice-covered conditions. A field survey was carried out in early March 2008 in a small meandering reach of the Neigette River, which is part of the catchment system of the Mitis River, Quebec. The friction imposed by the ice cover results in parabolic shaped velocity profiles. Reynolds stresses in the streamwise (u) and vertical (v) components of the flow show positive values near the channel bed and negative values near the ice cover, with 2 distinctive boundary layers with specific turbulent signatures. Vertically aligned stripes of coherent flow motions were revealed from statistics applied to space-time matrices of flow velocities. In open channel conditions, the macroturbulent structures extended over the entire depth of the flow whereas they were discontinued and nested close to the boundary walls in ice-covered conditions

Source

Article of periodic

published at : Earth surface processes and landforms / ISSN 0197-9337 / CODEN ESPLDB

Editor : Wiley, Chichester - ROYAUME-UNI (1981)

Millesime : 2013, vol. 38, no9 [pp. 937-946]

Bibliographic references : 1 p.

Collation : 8 fig.

Language

Anglais

INIST-CNRS, Cote INIST : 17355

Digital Object Identifier

Go to electronic document thanks to its DOI : doi:10.1002/esp.3334

Tous droits réservés © Prodig - Bibliographie Géographique Internationale (BGI), 2014
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