Author(s): Saeed-Reza Sabbagh-Yazdi; Babak Amin-Nejad
Linked Author(s):
Keywords: Spillway flow; Cartesian convective flux; Unstructured finite volume
Abstract: This paper presents the comparison between the numerical results of some techniques for computation of Cartesian convective fluxes on the boundaries of unstructured overlapping control volumes. The accuracy and efficiency of the techniques are evaluated by comparison of the numerical simulation of super-critical free surface flow in channels with non-parallel side walls. The utilized mathematical model for present computations is the set of shallow water equations which uses water depth and velocity components in horizontal plane in the continuity and equations of motion in horizontal plane. The governing equations are discretized utilizing cell vertex finite volume method on triangular meshes. The numerical oscillations of explicit solution procedure are damped out using either artificial viscosity scheme or upwind averaging fluxes at control volume boundary edges. The algorithm of evaluation of the fluxes at edges and artificial dissipation terms at nodes is adopted for unstructured meshes. Using all utilized techniques, no unwanted dissipation is introduced to the computed results and expected shockwaves are simulated accurately. The accuracy of the computational techniques are assessed by comparison between the numerical results and reported experimental measurements for super-critical flow in chute canals with expanded and contracted walls and using with. Finally, the simulation of sub and supercritical flow from dam reservoir over the geometrically complex chute canal of a real case is used to present the ability of the developed flow solver.
Year: 2005