Effect of Vegetation on Banks on Distributions of Velocity and Reynolds Stress under Accelerating Flow

Abstract

Vegetation on banks of natural channels exercises a significant influence on the flow structure and in turn on the velocity distribution as well as the distribution of Reynolds stress (the random turbulent fluctuations in fluid momentum). This study experimentally investigated the effect of vegetation on banks on accelerating flow in a gravel-bed flume. The results showed that in the presence of vegetation the Reynolds stress distribution became nonlinear and the velocity distribution took on a deformed S shape near the vegetated banks. In addition, vegetation on banks had more influence on the location of maximum velocity than had the aspect ratio. The log law fitted the data near the bed up to