ABSTRACT
This study describes the effects of porous patches on the local scour pools, using laboratory experiments and numerical computations. The local scour pool is developed when the flow blockage and the ratio of patch width to channel width are larger than 1.0 and 0.2, respectively. The depth of the scour pool increases with an increase in the flow blockage regardless of the submergence ratio. A twodimensional depth averaged model is presented and a sub-model for sand-sliding effect around the porous patches is combined. All experimental cases are replicated computationally and the results are compared with the experimental data. The results are in a reasonable agreement with measurements, which indicates that the scour pool is driven by an increase in bed shear stress due to two-dimensional flows. Based on experimental data, a predictive equation for the maximum scour depth around the porous patch in clearwater condition is proposed.
