Open Channel Flow with Water Plants

Abstract

The properties of flow in vegitated channels are investigated through laboratory experiments. The water plants are simulated by a group of cylinder with the same height, and the turbulence measurements are conducted. The equilibrium velocity in the vegitated region of water depth is determined by the bed slope, the concentration and the diameter of plants. The free surface flow over the vegitation is faster that the equilibrium velocity for the inside of vegitated region, and some mechanism plays a role of momentum exchange to accelerate the flow in the vegitated region near the interface with the free-surface flow region. In order to clarify this mechanism are inspected the mixing length, the correlation coefficient of the turbulence motion, the spectral charactersitics of velocity fluctuation and so on.