HIPÓTESIS EN MODELOS DE TRANSPORTE DE SEDIMENTO: EL PROBLEMA DE RIEMANN

Abstract

Sediment transport models in shallow water are typically assembled by the depth averaged Navier-Stokes and sediment conservation equations. Most of the published models assume hypothesis and simplifications during their process of derivation, making them easy to apply to current problems. However, taking some typical simplifications could not be valid in exceptional problems, such as Riemann problems. The dam-break problem is a widely known kind of Riemann problems. During the first stages of a dam-break the generated transient flow is sudden and abrupt. Thereby, the simplifications made for typical sediment transport problems need to be analyzed again; especially those ones related with the flow uniformity. The non-uniformity of the suspended sediment load of a flow in shallow water is normally neglected, as well as the flow turbulent stresses, in typical problems. Notwithstanding, as said above, its effect may not be negligible in dam-break cases. In consequence, this work carries an analysis about the importance of the correction factor of the suspended-load and the Reynolds’ stresses in a Riemann type problem with sediment transport.