Experimental Investigations of Scour Pools around Porous Obstructions

摘要

Paired impermeable or porous obstructions are used to create scour pool habitat. We investigated local scour pools created by paired porous obstructions using laboratory experiments. To examine the influence of porous obstructions on local scour depths and volumes, various densities in the porous obstructions, ratio of obstruction width to channel width and submergence ratio were evaluated. A local scour pool developed when the flow blockage (product of density in the porous obstructions and ratio of obstruction width to channel width) and the ratio of the obstruction width to channel width were ≥5.0 and ≥0.4, respectively. The depth of the scour pool increased with increasing flow blockage, while scour depth reduced as the submergence ratio increased. The scoured volume had a strong relationship with the scour depth around the porous obstructions. Results of the predictive equations were considered reliable for estimating the maximum scour depth and scoured volume around porous obstructions in clear-water conditions.