Properties of a streamwise turbulent flow field in an open two-stage channel

The results of the experimental studies, aimed at the recognition of the streamwise turbulent structure in a compound channel, are reported in this paper. Three sets of measurements with electromagnetic liquid velocity meter were used: one in a smooth channel, one with the rough overbank channels and the last one with the modelled high vegetation occurring on floodplains. The analyses included vertical distributions of local mean velocities, depth-averaged mean velocities, bed shear stresses, turbulent intensities, higher order velocity moments, autocorrelation and velocity spectra. Relevant turbulent temporal and spatial scales were evaluated. All the properties were investigated with special emphasis placed on the influence of roughness on them.