Hydrodynamic Behavior of Partly Vegetated Open Channels

The hydrodynamic response of turbulent flow in a compound wide rectangular open channel with a vegetated domain at the channel bank, in a channel corner and in a floodplain, to the vegetation density and diameter is discussed. To this end a phenomenological model was imbedded in an algebraic stress model with the vegetation modeled as an internal resistance that exerts drag force, produces energy of turbulence, and interferes with its anisotropy and length scale. Simple suggestions for some modeling problems associated with the presence of wide vegetated domains are used to yield the three-dimensional flow. Vorticity sources relaxation was implemented to smooth periodic behavior, and dissipation correction was introduced as a coordinate-invariant damping. With these, the results represent fully developed flow.