A kinetic interpretation of the section-averaged Saint-Venant system for natural river hydraulics.
Résumé
The classical Saint-Venant system is well suited for the modeling of dam breaks, hydraulic jumps, reservoir emptying, flooding, etc. For many applications, the extension of the Saint-Venant system to the case of non rectangular channels is necessary and this section-averaged Saint-Venant system exhibits additional source terms. The main difficulty of these equations consists in the discretization of these source terms. In this paper we propose a kinetic interpretation for the section averaged Saint-Venant system and we derive an associated numerical scheme. The numerical scheme~-- 2$^{nd}$ order in space and time~-- preserves the positivity of the water height, and is well-balanced. Numerical results including comparisons with analytic and experimental test problems illustrate the accuracy and the robustness of the numerical algorithm