Author(s): R. W. Jay Lacey; Andre G. Roy
Linked Author(s):
Keywords: Turbulence; ADV; Flow visualization; Gravel-bed rivers; Coherent flow structures
Abstract: This paper outlines and discusses the methodology and recent advances of a simultaneous in situ flow visualization and high-frequency velocity measurement technique. We demonstrate the advantages and disadvantages of the technique using a field study which investigated the hydrodynamics associated with the shear layer of an instream pebble cluster. In the study example presented, the flow visualization technique gave invaluable information on the physical processes associated with eddy shedding in the cluster wake. Through the combined method we are able to visually identify and characterise events estimated using ADV velocity measurements allowing for a much greater understanding of flow events. The two main disadvantages of the combined technique are the inadequate representation of the laterally directed coherent flow structures and the rapid dissipation of the flow tracer.
Year: 2007