Comparison between experimental and numerical results of 2D flows due to levee-breaking

Results of a laboratory investigation about the 2D flow field induced by a levee-break are compared with numerical results. A lateral breach is instantaneously opened in a tilting flume 10 m long subject to a constant discharge. This causes the inundation of an initially planar 2D dry surface. Measurements of water levels are made at various places around the breach, whereas the 2D velocity field is detected by means of ten acoustic transducers. Total discharge outflowing from the breach is also measured under stationary conditions. The same test conditions were numerically simulated using a mathematical model based on the 2D shallow water equations and solved by means of the well known McCormack finite difference scheme. Artificial dissipation terms have been introduced in order to avoid non-physical shocks and oscillations around discontinuities, whilst retaining the second order accuracy of the original scheme. Comparison with experimental data confirms that the model can be reliably used to describe 2D flows that could occur in nature due to dam or levee-breaking.