Prediction of Flow Hydraulics for Vegetated Channels

ABSTRACT SIMULATED dense vegetation with random blade arrangements and different blade flexibilities were used to determine the hydraulic properties of flow of small, non-submerging depths. With the water flowing among the randomly patterned vegetation blades, drag resistance becomes the dominant force that retards the flow. An equation of flow was established based on the momentum balance in the system. Experimental results were used to determine the coefficient of blade resistance, RD, and plotted in terms of blade width and flow depth Reynolds number respectively. Based on these plots and successful introduction of the three different sets of parameteric curves, a graphical method was developed to permit the determination of flow depth in the vegetated channel.