Two dimensional simulation of flow at open channel junctions

This study is interested in the flows at open channel junctions. The one-dimensional models usually used to characterize the hydraulic behaviour of these phenomenon are of empirical nature. The formulations used, often present a reduced field of validity. To overpass this constraint, we use the two-dimensional Saint Venant equations in order to numerically simulate the flows through junctions. An explicit second order finite volume scheme with Roe?s approximate Riemann solver is used to solve these equations, by using a triangular cells, in order to represent with accuracy irregular geometries. The model is verified by comparing the model output with analytical solutions. Two typical examples of dam break problems are presented in this article: the first through a combining junction and the second through a dividing junction.