Author(s): Fereshteh Bagherimiyab; Ulrich Lemmin; David Hurther; Peter D. Thorne
Linked Author(s): Ulrich Lemmin
Keywords: No Keywords
Abstract: Understanding sediment transport dynamics in the bottom boundary layer of unsteady open-channel flows is essential in order to be able to predict sediment movement which directly impacts on physical, chemical, biological and ecological processes in the water column. A study of the bottom boundary layer requires observations of the bed, flow and sediment movement. Recently developed acoustic techniques can provide measurements of these three parameters at high temporalspatial resolution. Here we employ acoustics to provide simultaneous and co-located measurements of (i) the three orthogonal components of flow using phase coherent techniques, and (ii) suspended sediment particles using acoustic backscatter. The quasi-instantaneous profiling capability of our instrument with the resolution of turbulence scales provides for detailed visualizations of the complex processes of unsteady boundary layer dynamics. This allows for an in depth investigation of bottom boundary layer physics in unsteady sediment-laden flow. The implications for sediment resuspension and transport are examined.
Year: 2009