Large-scale Experiment of compound channels with and without vegetation

Most fundamental studies on the hydrodynamics and morphodynamics of a vegetated channel are usually based on small-scale laboratory experiments. In this context, whether or not knowledge obtained from those small-scale physical models can be applied for rivers, channels, and estuaries, has not yet been determined. To obtain more insight into the exchange processes between the floodplain and the main channel regions, a small-scale and a unique large-scale physical model of compound channels with and without vegetation has been conducted at the TU Delft Water Lab and the Korea Institute of Civil Engineering and Building Technology - River Experiment Center (KICT-REC), respectively. The flow field within the vegetation region was measured using the Nortek Acoustic Doppler Velocity meter (ADV). The experimental results indicate the presence of large vortex structures at the interface of the floodplain and main channel regions. The experimental data were used to verify momentum exchange models at different scales. Furthermore, numerical models mimicking those experiments were constructed in Delft3D. Finally, the experimental results were compared with the numerical results, showing the ability of the state-of-the-art model.