Modeling Investigation On The Flow Resistance And Width Adjustment Of Vegetated Floodplain In Compound Channel

This paper is about physical modeling investigation on river width adjustment process of compound channel with vegetated floodplains. Different materials are used to simulate different type of vegetations. By using movable velocity instrument and indicator of mud-Water interface to measure velocity and channel morphological changes, the effect of the vegetations planting on the floodplains on flow internal structure is studied.This paper summarized the achievements about flow characteristics of vegetated open channel and river width dynamic adjustment roundly. The systemic model tests of mobile bed with vegetated floodplain are carried out. Velocity distribution and width adjustment process are subtly measured, and the theoretic research and numerical modeling are done. The cross sections of compound channel are divided into 3 typical zones: main channel, floodplain and the area between main channel & floodplain, each of them was discussed respectively. The characteristic of coefficient of roughness on river channel with and without vegetations are investigated specially, as well as relations between the submerged deflection height and roughness coefficient of vegetated channel, which enrich the research findings of such subjects.Finally, this paper takes an outlook about the construction of ecotypes watercourse.