A methodology to project ADCP data for detecting secondary flows in river bends

VIONNET CA; GALLEGO M; TARRAB L; RODRÍGUEZ A

Cayastá, Santa Fe, Argentina

Workshop; Morphodynamic Processes in Large Lowland Rivers; 2007

NCED (the National Center for Earth-surface Dynamics – a National Science Foundation Science and Technology Center) - FICH, UNL

In this short communication, a simple methodology to project the cross-flow components measured with an Acoustic Doppler Current Profiler (ADCP) mounted on a boat, also equipped with a geodesic GPS (Global Positioning System), is presented. It is then established that regardless of the cross-section orientation, whenever centrifugal effects are up to the leading order in the cross-wise plane (whose intensity depends on the ratio channel width to water depth), the cross-flow or secondary cell is always captured. The field measurements were taken at the outlet of the Colastiné River, nearby Santa Fe city, Argentina, where the flow diverts in two branches, one of them forming an acute bend.