Abstract
In order to design an environmentally-friendly river structure, the flow and fields around a rubble mound weir and groin were investigated. In a physical model experiment, the flow inside the structure was visualized by adjusting the refraction indexes between the working fluid and the rubble's materials. Velocity vectors were obtained by means of PIV. Mass and momentum exchange between the open channel flow and the rubbles' porous media were found to be predominant around the up- and downstream corners of the weir and the groin. Both the turbulent intensity and Reynolds stress were also significant in these areas due to intensive momentum exchange. On the other hand, in the structure, turbulence properties were mainly influenced by the arrangement of the rubble and pores in the structure.
