Laboratory experiments were conducted using a two-component electromagnetic current-meter and a particle-image-velocimetry (PIV) to clarify the interaction between main flow and flexible artificial vegetation, which was attached to the central bottom of an open channel. In addition, interception plate 1mm thick was placed at the one-sided vegetation interface along the main flow direction.
Results show that in the main flow region of the equilibrium state, horizontal components of the secondary currents take the directions toward the vegetation zone near the bottom and toward the non-vegetation zone near the surface. From the measurements, it was shown that this thin plate significantly suppressed water surface oscillations, horizontal periodical velocity variations and spanwise momentum transport from main flow region to vegetation zone.