Search results for "Bed form"
showing 2 items of 2 documents
Experimental Analysis of Horizontal Turbulence of Flow over Flat and Deformed Beds
2015
Abstract Laboratory experiments in a straight flume were carried out to examine the evolution of large-scale horizontal turbulent structures under flat-bed and deformed-bed conditions. In this paper, the horizontal turbulence of flow under these conditions is analyzed and compared. The conditioned quadrant method is applied to verify the occurrence of turbulent events. The distributions of horizontal Reynolds shear stress and turbulent kinetic energy are also presented and discussed. Results show the occurrence of an “initial” sequence of horizontal vortices whose average spatial length scales with the channel width. Under deformed-bed conditions, this spatial length does not change.
Sediment-flow interactions and effects on bed forms mechanism
2009
Recent experimental works conducted in mobile bed rectilinear flume seem to verify the existence of a correspondence between the spatial periodicity of horizontal turbulent structures evolving in streamwise direction and the wavelength of bed forms (alternate bars) observed on the bed. In this study, the effect of the variation of the bed roughness conditions on the evolution of such horizontal turbulent structures is analyzed. Peculiar results obtained by using flow velocity data collected along the flume both with flat bed and with deformed bed are reported.