In this paper, effects of the cross shore and groyne wall slopes on flow parameters around an impermeable groyne were considered using a three-dimensional numerical CFD model (i.e., FLUENT). The k-ε turbulence model was used to evaluate the Reynolds stresses. The model was first applied to a vertical groyne on a flat bed and the model results were compared with the relevant experimental data. The results of this numerical test showed good agreements with the corresponding experimental measurements, in terms of water elevation, velocity magnitudes and reattachment length. The model was then applied to a series of structures with different lateral wall slopes on various cross sectional bed slopes. The numerical model results revealed that by increasing the cross shore bed slope in any case of the structural slopes, the magnitude of the maximum velocity and bed shear stresses decreased. These values decreased further as the structural slope reduced.
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