MEAN AND TURBULENCE STRUTURES OF OPEN-CHANNEL FLOWS WITH SUBMERGED VEGETATION

In this study, the mean flow and turbulent structures of the open-channel flows with the submerged vegetation was explored. For this, laboratory flume experiments are conducted with model vegetation without foliage. Wooden dowel is used for rigid vegetation, and polyethylene film is used for flexible vegetation. Other properties of model vegetation are made the same. Mean and fluctuation velocities are measured using the laser Doppler anemometer. From the measured data, the vertical profiles of mean velocity, turbulent intensity, Reynolds shear stress are obtained. The general profiles for mean velocity and turbulent intensity is suggested, and the profiles of Reynolds shear stress were investigated. The impact of stem flexibility was also investigated. It was shown that mean velocity and Reynolds shear stress can hardly distinguished from that with rigid vegetation. However, turbulent intensity profiles were affected by stem flexibility.