Einflüsse auf die Geschiebeaufteilung an spitzwinkligen Gerinneverzweigungen

In hydraulic engineering discharge diversions along channels with branches regularly occur in the field of bedload sedimentation engineering. Due to the curvature of a channel, a channel diversion causes secondary currents. Compared to the flow distribution, the bedload closely follows the near-bed flow lines and is thus disproportionately guided into the diverting channel; this is called the “Bulle effect”. The bedload transport into the straight channel increases with increasing discharge fraction. This study includes the analysis of the superimposing effect of cross-sectional aspect ratio, since the bedload distribution in the straight channel increases with increasing aspect ratio, which is taken into account in a new analytical approach. Furthermore, the effect of different bedload material is compared for sand and light weight granulate showing similar deposition distributions as long as discharge distribution and aspect ratio are identical. The bedload distribution is also investigated under the influence of additional deflection structures.