Author(s): C. Dorfmann; H. Knoblauch
Linked Author(s):
Keywords: Reservoir hydraulics; ADCP velocity measurements; 2-D and 3-Dnumerical model; Eddy Viscosity; Roughness; POW and SOU scheme
Abstract: This paper focuses on the calibration of 2-D and 3-D numerical models and its necessity with respect to the flow field in a large reservoir. For this purpose an ADCP velocity measurement campaign has been carried out. The project area of the reservoir is marked by a 200 m wide gorge portion 3500 m upstream of the weir which merges into a 1000 m expanded area with change in water depth from 5 to 20 m. The results indicated distinct flow patterns of a main stream entering the reservoir with expanded zones of backflows as well as still water at the orographic left side of the reservoir; summarised, a large anticlockwise vortex. In the 2-D calculations the flow pattern in the wide area depended highly on the applied value for the constant Eddy Viscosity. On the other hand in the 3-D calculations the resulting velocity distribution was highly sensitive to the applied roughness value and numerical discretization scheme.
Year: 2009