Abstract
The resistance law for flow on river-beds with vegetation is investigated experimentally and theoretically. The results of basic experiments with artificial vegetation indicate that when the vegetation density is less than a certain level, the flow passing through the vegetation is considerably affected by the river-bed condition. A numerical model for the vertical velocity distribution and the mean flow velocity is derived, based on Reynolds stress reduction model and Prandtl's mixinglength theory. The validity of this model is demonstrated through its comparison with the experiments conducted by the authors.
