In order to understand more clearly hydrodynamics of rubble mound weirs and groins as environmentally-friendly river structures, the flow fields around them were experimentally investigated. In a physical model experiment, the flow inside the structure was visualized by adjusting the refraction indexes between the working fluid and the materials of the rubble. Velocity vectors were obtained by means of PIV. It was found that mass and momentum exchange between the main flow and the rubble's porous media was predominant around the upstream and downstream corners of the weir and the groin, where streamline was rapidly contracted. Therefore, turbulence energy was significantly produced there, which eventually caused a high intensity of turbulence. The turbulent structure in the rubble mound was almost independent of ambient flow fields, and was also primarily influenced by the rubble-pore arrangement.
展开▼
