THREE-DIMENSIONAL MEASUREMENTS WITH LASER DOPPLER ANEMOMETERS IN UNSTEADY DEPTH -VARYING COMPOUND OPEN-CHANNEL FLOWS

摘要

An unsteady depth-varying open-channel flow is one of the most important flows in hydraulic engineering and therefore these hydrodynamic characteristics should to be investigated in detail. Recently, several highly-accurate turbulence measurements have been conducted in unsteady two-dimensional(2-D) open-channel flows with a two-component laser Doppler anemometer (LDA), and they offer a very valuable database of the observed turbulent structures that is needed to develop numerical simulations. However, as for three-dimensional (3-D) structures of unsteady open-channel flows that are the most important compound rivers in flood, no accurate database is available as yet. So, in this study, 3D turbulence measurements with LDA were conducted in unsteady compound depth-varying open-channel flows and these results.