NUMERICAL STUDY ON TURBULENT FLOW OVER RIGID VEGETATION-COVERED BED IN OPEN CHANNELS

Open channel flow over rigid vegetation is analyzed numerically by horizontaly averaged Reynolds equations based on k-e turbulence model. Not only uniform flow over vegetated bed but also a transitional flow from area over a smooth bed to area over vegetated bed is studied. The experiments were previously conducted for the former case. For the latter case, the flow experiments are conducted. The experimental data are well described by the numerical model. Furthermore, the effect of the vegetation density on the turbulent structure is investigated with numerical prediction of flow by the present model.