...
A full description of equations and manual is given in Delft Cluster report Oeverstabiliteit bij verdieping Waterbodems, chapter 3.
The required upper boundary is defined by a slowly retrograding “breach”: a local small and steep slope irregularity, gradually retrograding upslope generating a small but steady sandflow that may transform into an erosive and turbulent sand-water density flow. Actually the model is quasi-stationary taking into account the regression velocity that is defined by the sand properties. The erosion is described as a sediment flux at the bed with a semi-empirical model as a function of bed shear stress, slope and sand properties. This model was calibrated with experiments in a tilting flume with fine 120 mu sand resulting in erosion velocities measured perpendicular to the bed up to 5 mm/s with flow velocities up to 2.5 m/s, Ref. [Winterwerp et al, 1992]. The model is derived for high volumetric sediment concentrations taking into account the effect of density differences on the momentum equation (no Boussinnesq approximation applied). Non-steady effects such as TC head and tail development are not described, nor vertical development or development in width, curves etc.
...