Author(s): Ursula Stephan; Marinko Nujic
Linked Author(s): Ursula Stephan
Keywords: Stepped spillway; Physical model; Numerical model; 2-D-modeling; Free surface flow
Abstract: Nowadays, according to the current state of the art, 2-D flow models are often used in the field of hydraulic engineering to investigate multidimensional flow conditions, such as flood run-off in floodplains. Nevertheless, physical models are still built to reproduce highly complex flow conditions and to answer questions of dimensioning. For a physical model, it means considerable efforts to modify the model geometry, whereas these variations and, thus, also the investigation of effects of different measures on flow conditions can be done rather easily in a numerical model. This means an important advantage for numerical models compared to physical models. Therefore, the 2-D flow model HYDRO_AS-2D was applied to a complex geometry with strong variations in bottom topography, a curved and stepped spillway. The results of the 2-D flow model were compared to the results of a physical model of the same geometry, to investigate, whether a 2-D numerical model can replace a physical model. It has been shown, that 2-D numerical models are nowadays capable to cope with different and very complex hydraulic situations. The difficulties or inaccuracies may however arise due to shallow water assumptions when trying to model some kinds of structures. One possible way to solve such kind of problems effectively would be to model only structures in a physical model and use the gained experimental data to calibrate a numerical model (hybrid type of model).