Abstract
Flow over flexible vegetation-covered bed was investigated by the flume experiment and the numerical analysis. The experimental results showed that deformation of plants reduces flow resistance and waving motion of plants increases flow resistance. The numerical model of which a k-ε turbulence model is coupled by a model of deformation of plants explanied the reduction of the flow resistance caused by the deformation of plants. The model also clarified the relationship between flow condition and quantity of deformation. The waving motion causes hetrogenety of vegetation layer and it brings an additional momentum transfer. It is supposed that the additinal momentum transfer is the causes of the increase of flow resistance. Finally, flow resistance and shear stress acting on a bed in some kinds of flood plain vegetation was estimated.
