Author(s): Mario Oertel
Linked Author(s): Mario Oertel
Keywords: No Keywords
Abstract: The presented paper deals with influencing parameters for flow resistance and resulting energy dissipation processes on cross-bar block ramps. Cross-bar block ramps are a nature-like solution to conquer large river bottom steps with fish climb capabilities. Boulder rows lateral to the main flow direction form single basins, while the flow characteristics change with increasing discharges. Thereby, several parameters influence the hydraulic processes on the structure, but with significant differences compared with regular rough flow conditions. This paper presents results for investigated parameters with major influence on the flow regimes. Therefore, a sensitivity analysis within a physical scaled model is conducted. Model runs have been carried out in a tilting flume with varying slopes and discharges. Next to the discharge and slope, geometrical boundary conditions of the arranged cross-bars are in the main focus of investigation. The cross-bar distance, the cross-bar height, the cross-bar form and the base material’s diameters have been varied within several model runs. The results quantify influencing parameters in detail and present an integration method for current approaches to determine friction factors and energy dissipation on cross-bar block ramps.
Year: 2012