The evaluation of the net flux of sediments entering/leaving the flow over an erodible bed (entrainment) plays a key role in the description of solid transport. Furthermore, the expression of the entrainment is required as one of the closure relations of several recent morphological models suited for the analysis of fast erosional transients, as dam break over a loose bed. However, the choice among the formulations proposed in the literature for erosion/deposition (entrainment) evaluation is far from being straightforward. In order to investigate the effect of the choice of different entrainment/deposition formulas, in the present paper a comparison among some of the existing formulations, either deduced from experimental investigations or based on theoretical analysis, has been performed. As a benchmark, a well documented laboratory experiment of dam break over an erodible bed has been selected from the literature, while a two-phase morphodynamical model has been employed to simulate the process. The comparison between numerical simulations and experimental data highlights the different performances and limitations of the considered formulations.
Comparison among different entraiment/deposition functions in the simulation of a 1D dam-break.
DI CRISTO, Cristiana
2010-01-01
Abstract
The evaluation of the net flux of sediments entering/leaving the flow over an erodible bed (entrainment) plays a key role in the description of solid transport. Furthermore, the expression of the entrainment is required as one of the closure relations of several recent morphological models suited for the analysis of fast erosional transients, as dam break over a loose bed. However, the choice among the formulations proposed in the literature for erosion/deposition (entrainment) evaluation is far from being straightforward. In order to investigate the effect of the choice of different entrainment/deposition formulas, in the present paper a comparison among some of the existing formulations, either deduced from experimental investigations or based on theoretical analysis, has been performed. As a benchmark, a well documented laboratory experiment of dam break over an erodible bed has been selected from the literature, while a two-phase morphodynamical model has been employed to simulate the process. The comparison between numerical simulations and experimental data highlights the different performances and limitations of the considered formulations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
